Sökning: "propulsion"

Visar resultat 11 - 15 av 182 avhandlingar innehållade ordet propulsion.

1. 11. High Frequency Model of Electrified Railway Propulsion System for EMC Analysis

   Författare :Kelin Jia; Rajeev Thottappillil; Hans Bängtsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electromagnetic compatibility; railway; propulsion system; multitransmission line; ac motor modeling; vector fitting; fast transient;

   Sammanfattning : A model of the electrified railway propulsion system working in a wide frequency range is studied in this thesis. The high frequency modeling is the first stage to study and predict the Electromagnetic compatibility (EMC) problems in the electrified railway propulsion system, which are safety and reliability issues of high concern. LÄS MER

3. 12. High-Temperature Microfluidics for Space Propulsion

   Författare :Ville Lekholm; Klas Hjort; Anders Persson; Lena Klintberg; Herbert Shea; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk fysik med inriktning mot mikrosystemteknik; Engineering Science with specialization in Microsystems Technology;

   Sammanfattning : In this thesis, microfabrication methods and tools for analysis of heated cold-gas microthrusters are presented, with the aim of improving their reliability and performance. Cold-gas thrusters operate by accelerating pressurized gas through a nozzle. LÄS MER

4. 13. Supervisory control of complex propulsion subsystems

   Författare :Dhinesh Vilwanathan Velmurugan; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Look-ahead control; engine control; exhaust after-treatment; supervisory control;

   Sammanfattning : Modern gasoline and diesel combustion engines are equipped with several subsystems with the goal to reduce fuel consumption and pollutant exhaust emissions. Subsystem synergies could be harnessed using the supervisory control approach. Look-ahead information can be used to potentially optimise power-train control for real time implementation. LÄS MER

5. 14. Flywheel in an all-electric propulsion system

   Författare :Johan Lundin; Hans Bernhoff; P-O Västeräng; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flywheel; electric vehicle; hybrid vehicle; power management; energy storage;

   Sammanfattning : Energy storage is a crucial condition for both transportation purposes and for the use of electricity. Flywheels can be used as actual energy storage but also as power handling device. Their high power capacity compared to other means of storing electric energy makes them very convenient for smoothing power transients. LÄS MER

7. 15. On Design of a Compact Primary Switched Conversion System for Electric Railway Propulsion

   Författare :Tommy Kjellqvist; Stefan Östlund; Alfred Rufer; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Isolated AC DC converter; Mutual commutation; Soft Switching; Cyclo converter; Medium-Frequency Transformer; Electric Railway Propulsion; Electrical engineering; Elektroteknik;

   Sammanfattning : In this thesis, a compact and light primary switched conversion system for AC-fed railway propulsion is investigated. It is characterized by soft switching of all converter stages and a source commutated primary converter comprising series connected valves. LÄS MER