Search for dissertations about: "traction power"

Showing result 1 - 5 of 60 swedish dissertations containing the words traction power.

2. 1. On Gate Drivers for MOS-Controlled Power Devices and dv-dt Filters for Train Traction Converters

   Author : Erik Velander; Hans-Peter Nee; Francesco Iannuzzo; KTH; []
   Keywords : Power semiconductor devices; DC-AC power converters; Silicon carbide; Insulated gate bipolar transistors; P-i-n diodes; Schottky diodes; Traction motors; Power MOSFET; Krafthalvledare; DC-AC kraftomvandlare; kiselkarbid; IGBT; P-i-n dioder; Schottky dioder; traktionsmotorer; Effekt-MOSFET; Electrical Engineering; Elektro- och systemteknik;

   Abstract : In this thesis, low-loss gate-drive solutions and a proposed dv/dt-filter have been investigated with focus on train traction converters with dv/dt constraints.By using the silicon carbide (SiC) junction field-effect transistor (JFET), the switching losses can be significantly reduced compared to the commonly used insulated-gate bipolar transistor (IGBT), but complex gate-driver solutions are required for high utilization in terms of loss reduction. READ MORE

4. 2. On Rolling Variators, A study of power transmitting rolling variators when changing speed ratio

   Author : Göran Brännare; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; friction drives; traction drives; variators; traction; CVT; speed ratio change; rolling traction trnasmissions; continously variable transmissions; rolling contact drives; transmission ratio change;

   Abstract : The introduction of the concept Rolling Variators is proposed for rolling contact continuously variable transmission.A theoretical study of rolling variators when changing the speed ratio during power transmission is presented. READ MORE

5. 3. Integrated In-Wheel Motors for Low Power Traction Application

   Author : Prakashraj Kasinathan; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electric golf cart; integral-slot; force density; flux-linkage; traction motors; forklift trucks; direct-drive; electric wheelchairs power wheelchairs; low speed machines; fractional-slot;

   Abstract : This thesis is primarily concerned with the practical limits, imposed by magnetic saturation and thermal considerations, of the force density in low-speed permanent-magnet electric machines. The practical force density values obtainable in integral- and fractional-slot machines are determined. READ MORE

6. 4. On soft-switching isolated AC/DC converters without auxiliary circuit

   Author : Staffan Norrga; Stefan Östlund; Rik De Doncker; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical power technology; voltage source converter; cycloconverter; isolated converter; medium frequency transformer; soft switching; modulation; commutation; wind power; electric traction; Elkraftteknik; Electric power engineering; Elkraftteknik;

   Abstract : The thesis is concerned with a class of power electronic converter systems that permit bidirectional AC/DC conversion with galvanic separation of the AC and DC sides by a transformer operating at elevated frequency. The systems consist of a capacitively snubbered voltage source converter and a cycloconverter, separated by the mentioned transformer. READ MORE

7. 5. Continuously Variable Split-Power Transmissions with Several Modes

   Author : Per Mattsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; continuously variable transmission; variator; speed ratio range; ratio coverage; traction drive; mode shift; CVT; planetary gear; power split; IVT; infinitely variable transmission; epicyclic gear train; hydrostatic variator;

   Abstract : A continuously variable transmission (CVT) of split-power design consists of a variator and an arrangement of planetary gears. A black box model describing such transmissions is presented. The model can be used for synthesis as well as loss-free analysis of split-power CVT concepts in general. READ MORE