Search for dissertations about: "AC machines"

Showing result 1 - 5 of 9 swedish dissertations containing the words AC machines.

  2. 1. Iron Losses in Electrical Machines - Influence of Material Properties, Manufacturing Processes, and Inverter Operation

    Author : Andreas Krings; Juliette Soulard; Oskar Wallmark; Annette Mütze; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC machines; cobalt-iron; eddy current losses; electrical steel sheets; inverter-fed machines; iron alloys; iron loss measurements; machine design; magnetic hysteresis; magnetic losses; magnetic materials; nickel-iron; permanent magnet machines; silicon-iron; soft magnetic composites; slot-less machines; soft magnetic materials; thermal effects.; Electrical Engineering; Elektro- och systemteknik;

    Abstract : As the major electricity consumer, electrical machines play a key role for global energy savings. Machine manufacturers put considerable efforts into the development of more efficient electrical machines for loss reduction and higher power density achievements. READ MORE

  4. 2. Investigation of AC electrical machine stators with fractional conductor windings

    Author : Henrik Grop; Juliette Soulard; Yujing Liu; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; windings; leakage; large machines; induction motor construction; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Abstract : Industry always searches the least expensive solution for a machine design. Therefore, there is a need for integrating different customer ordered machines within the same frame, while keeping the foundation of the mechanical design constant. READ MORE

  5. 3. Modeling and Control of VSC-HVDC Links Connected to Weak AC Systems

    Author : Lidong Zhang; Hans-Peter Nee; Alan Wood; KTH; []
    Keywords : Control; modeling; multivariable feedback control; HVDC; power systems; stability; subsynchronous torsional interaction; voltage-source converter; weak ac systems;

    Abstract : For high-voltage direct-current (HVDC) transmission, the strength of the ac system is important for normal operation. An ac system can be considered as weak either because its impedance is high or its inertia is low. READ MORE

  6. 4. On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes

    Author : Fredrik Carlsson; KTH; []
    Keywords : Rolling mill; Blast furnace; Power Quality; Synchronous machine; Asynchronous machine; Voltage sag; Voltage interruption; Ride-through; Process disturbances; Simulation; Modelling;

    Abstract : During the last decade, power quality has been recognised asa global problem. Among different types of power qualityproblems, voltage sags have been identified to be one of themost severe problems for different process industries. The mostcommon reason to voltage sags is lightning strikes in powerlines. READ MORE

  7. 5. Power Control Systems in a Flywheel based All-Electric Driveline

    Author : Janaína Gonçalves de Oliveira; Hans Bernhoff; Mats Leijon; Torbjörn Thiringer; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flywheels; batteries; electric vehicles; control systems; power electronics; electric machines; efficiency.; Electric power engineering; Elkraftteknik; Electrical engineering; Elektroteknik; Electronics; Elektronik; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : Flywheel systems are attractive in hybrid and electric vehicles due to their ability to handle power during acceleration and braking. The combination of a flywheel device with a battery source has several advantages such as high peak power capacity, high energy density and reduction in the number of charge/discharge cycles of the battery. READ MORE