Sökning: "Electromagnetic Theory"

Visar resultat 16 - 20 av 126 avhandlingar innehållade orden Electromagnetic Theory.

1. 16. Electromagnetic Analysis of Hydroelectric Generators

   Författare :Martin Ranlöf; Urban Lundin; Georg Traxler-Samek; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Contra-rotating rotors; damping torque; damper winding; finite element method; hydroelectric generators; permeance model; pole shoe shape; rotational losses; single machine infinite bus; slot ripple; synchronizing torque; synchronous machines; voltage waveform.; Engineering physics; Teknisk fysik; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : Hydropower maintains its position as the most important source of renewable electric energy in the world. The efficiency of large hydropower plants is unsurpassed, and after more than hundred years of development, the technology is mature and highly reliable. LÄS MER

3. 17. On the Design of Ultra-fast Electro-Mechanical Actuators

   Författare :Ara Bissal; Göran Engdahl; Torbjörn Lembke; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electro-mechanical drive; Circuit breakers; HVDC transmission; Eddy currents; Finite element; Electromagnetic; Thermal; Mechanical; Coils; Armature; Image motion analysis.;

   Sammanfattning : The continuously increasing demand for connecting electric grids with remote renewable energy sources such as wind power and photovoltaic cells has rekindled interest in high voltage direct current (HVDC) multi-terminal networks. Although HVDC networks have numerous benefits, their adoption relies entirely on the availability of HVDC circuit breakers which, compared to traditional alternating current circuit breakers, have to operate in a time frame of milliseconds. LÄS MER

4. 18. On signal processing and electromagnetic modelling : applications in antennas and transmission lines

   Författare :Jonas Lundbäck; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vector sensors; Statistical signal processing; Antennas; Directional Coupler; Tranmission lines; Partial discharge;

   Sammanfattning : This doctoral thesis is comprised of five parts. The first three parts concern signal processing and electromagnetic modelling of multiport antennas. The last two parts concern signal processing and transmission line theory applied to wave splitting on transmission lines. LÄS MER

5. 19. Cubic Response Theory and the Electromagnetic Properties of Ground and Excited States

   Författare :Dan Jonsson; Aage E. Hansen; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis is devoted to the study of analytical response theory up to third order and its application to electromagnetic properties of ground and excited states. Computationally tractable expressions for the cubic response function for SCF and MCSCF wave functions have been derived and implemented in a computer code. LÄS MER

7. 20. Systematic Antenna Design Using the Theory of Characteristic Modes

   Författare :Zachary Miers; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Theory of Characteristic Modes; Antenna Design; Antenna; Characteristic Modes; Computational Electromagnetics; MIMO Systems; MIMO Antenna; MIMO; Mutual Coupling; Mobile Antenna;

   Sammanfattning : The day Faraday moved a magnet in and out of a wire loop and detected the time-varying magnetic field, the first wireless transmitter / receiver system was created and the world was changed forever. However, it took almost fifty years for Heinrich Hertz to use Maxwell's equations and Faraday's insights in his professorship at Karlsruhe to create the first electromagnetic wireless communication system using a spark gap dipole transmitter and a loop antenna-based receiver. LÄS MER