Sökning: "low speed machines"

Visar resultat 11 - 15 av 40 avhandlingar innehållade orden low speed machines.

1. 11. Faults detection and diagnosis for three phase induction machines

   Författare :Mohammed Obaid Mustafa; George Georgoulas; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reglerteknik; Control Engineering;

   Sammanfattning : Three phase induction motors have been intensively utilized in industrial applications, mainly due to their efficiency and reliability. These motors have good properties such as: increased stability and robustness, durability, large power to weight ratio, low production costs and controllability easiness. LÄS MER

3. 12. Analysis and Reduction of Parasitic Effects in Induction Motors With Die-Cast Rotors

   Författare :Alexander Stening; Chandur Sadarangani; Nicola Bianchi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aluminium rotors; asynchronous torques; copper rotors; die-cast rotors; induction machines; inter-bar currents; modulated rotors; starting torque; stray losses; synchronous torques;

   Sammanfattning : This thesis presents a study of inter-bar current effects on induction motors with die-cast aluminium and die-cast copper rotors. The parasitic effects introduced by these currents are analyzed and possible solutions to these problems are presented. This is realized by developing analytical tools for the simulation of inter-bar current effects. LÄS MER

4. 13. Efficiency Analysis of Drive-train for an Electrified Vehicle

   Författare :Ali Rabiei; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drive cycles; Current vector control; Vehicle applications; Silicon carbide; Power electronics; Energy efficiency; Loss calculation; Electric machines;

   Sammanfattning : In this PhD thesis, various solutions to improve the energy efficiency in the electrical drive-train of an electrified vehicle such as modifications of the propulsioninverter or control of the electric machine, are proposed and their benefits arequantified from an energy efficiency point of view. The efficiency analysis isbased on modeling of a power electronics inverter, an electric machine and a battery in various drive cycles for an electrified vehicle. LÄS MER

5. 14. Cases of coupled vibrations and prametric instability in rotating machines

   Författare :Jean-Claude Luneno; Ilmar Santos; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : The principal task in this research project was to analyse the causes and consequences of coupled vibrations and parametric instability in hydropower rotors; where both horizontal and vertical machines are involved. Vibration is a well-known undesirable behavior of dynamical systems characterised by persistent periodic, quasi-periodic or chaotic motions. LÄS MER

7. 15. Multitemporal Spaceborne Polarimetric SAR Data for Urban Land Cover Mapping

   Författare :Xin Niu; Yifang Ban; Laurent Ferro-Famil; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; RADARSAT-2; Spaceborne; Polarimetric SAR; Urban Land cover; Object-based Rule-based Classification; Support Vector Machines; Contextual; Stochastic Expectation-Maximization; Markov Random Field.;

   Sammanfattning : Urban land cover mapping represents one of the most important remote sensing applications in the context of rapid global urbanization. In recent years, high resolution spaceborne Polarimetric Synthetic Aperture Radar (PolSAR) has been increasingly used for urban land cover/land-use mapping, since more information could be obtained in multiple polarizations and the collection of such data is less influenced by solar illumination and weather conditions. LÄS MER