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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Návrh vysokootáčkového asynchronního motoru / Design of high-speed induction motor

Svoreň, Jan January 2012 (has links)
This work deal with troubleshooting of problem parts of high-speed induction machines. Introduction is about conception of induction machines with reference to construction specialities due to high rpm and because machines are fed by inverter. Next part is focused to design problems. A classical induction machine was measured to determination change of various losses in classic and high-speed induction machines. The computation of laboratory sample high-speed motor was specified for calculation of effective resistance and leakage reactance of solid-steel rotor with copper layer. The results of numerical calculation were validated by using finite elements method and machine design was adjusted for improving operation characteristic.
272

Laboratorní soustrojí s asynchronním a stejnosměrným motorem / Laboratory machine-set with induction and DC machine

Hudák, Ondřej January 2012 (has links)
The work addresses the design and implementation of a universal laboratory workstation designed to teach a course on electrical drives. Workplace will be formed sets consisting of DC motor with permanent magnet on a 400W power supply voltage of 24V and induction motor with 180W power on 3x24V. The engines are connected through a flexible shaft coupling. The asynchronous motor is located on the extended shaft resolver for scanning speed and rotor position. Both engines will be supplied from the transistor inverters. The workplace will be designed for maximum clearness and resistance to damage by improper handling.
273

Simulace pohonu hybridního automobilu / Simulation of hybrid car drive

Byrtus, Jiří January 2013 (has links)
This thesis deals with analysis of electric drive parts from hybrid electric vehicle, namely interior permanent magnet synchronous motor and inverter with control. First part describes a basic theory. Further, motor and inverter computer models are shown, specified simulations are performed on this models. Results are compared with values measured on real machines from accessible literary sources.
274

Snížení zapínacího proudu transformátoru / Reducing transformer inrush

Zoufalý, Marek January 2015 (has links)
In this thesis is described the function and design of the transformer designed on ferromagnetic core, composed of transformer sheets. It is explained a transient inrush current of the transformer. In this work is inserted voltage and current waveforms, designed printed circuit board, serving to reduce the inrush current.
275

Řídicí jednotka pro BLDC motor / Control unit for BLDC motor

Krejčí, Ondřej January 2014 (has links)
This master„s thesis elaborates with EC motors problematic. There are described essential features of brushless DC motors, their principles, construction and methods for rotor position detection. There are mentioned commonly used control algorithms of EC motors including theory of three-phase convertors. This thesis also contains a complex design of the universal convertor for EC motor and its practical implementation. Power parts losses calculation, heat-sink calculation and measurements at the convertor prototype are also described in this thesis.
276

Laboratorní ukázka řízení asynchronního motoru / Laboratory example of synchronous motor control

Vrtal, Václav January 2010 (has links)
This thesis deals with the speed control three-phase asynchronous motor revolutions by a frequency converter Sinamics G110 by way of the programmable automat SIMATIC S7-224XP. Control of programmable automat is realized the operator panel TP 177 micro. Communication between the PLC and frequency converter is realized by USS protocol on bus RS-485. The main goal was to design and implement software, which would allow operation to choose different variations of speed time histories (sinusoid, saw, jump course, etc.), but also the possibility to control the position. Another goal was to create graphical environment for the operator panel that allows manual control, editing and monitoring of engine speed. The last goal was to evaluate the results and summary of findings during commissioning.
277

Proaktivní diagnostika a monitorování stavu trojfázových asynchronních motorů v průmyslovém podniku / Proactive diagnostics and monitoring of the state of three phase asynchronous motors in industrial company

Holub, Ondřej January 2016 (has links)
This master thesis deals with the proactive diagnostics and monitoring of state of the three phase asynchronnous motors in industrial company Bosch Diesel Jihlava. In master thesis is designed diagnostics system based on the selected suitable diagnostics methods and other appropriate process monitors the status of these technical equipments.
278

Snížení zapínacího proudu transformátoru / Reducing transformer inrush

Zoufalý, Marek January 2016 (has links)
In this thesis is described the function and design of the transformer designed on ferromagnetic core, composed of transformer sheets. It is explained a transient inrush current of the transformer. In this work is inserted voltage and current waveforms, designed printed circuit board, serving to reduce the inrush current.
279

Návrh a realizace aktivního trojfázového usměrňovače / Concept of three-phase active rectifier

Bareš, Jiří January 2016 (has links)
This work deals with three-phase active rectifier control. In first, theoretical part it describes several control strategies with focus on voltage oriented control. For this type of control a design is worked out, and created model and its simulation is described. Second, practical part deals with realisation on microcontroller TMS320F28335, which is main processing unit of device lent by company Elcom. Therefore in this part abilities and settings of the controller along with developped control algorithm are described. Reached results of measurement are then presented and in the conclusion they are evaluated.
280

Utveckling av laboration om trefastransformatorn : En studie om transformatorer / Development of three phase transformer lab : A study about transformers

Al-Breihi, Mohammed January 2014 (has links)
Examensarbetet har utforts pa uppdrag av enheten for Data- och Elektroteknik pa skolan for Teknik och Halsa, KTH. Denna studie om transformatorer omfattar deras funktioner och anvandningsomraden, hur de ar uppbyggda, hur karnan och lindningarna som ar transformatorns viktigaste delar ar uppbyggda, vilka materiel som anvands vid konstruktion av dessa samt vilka typer det finns av dem beskrivs i rapporten. Vidare beskrivs flera olika transformatortypers funktioner och anvandningsomraden. Eftersom en viktig del av studien varit pa vilka satt transformatorer kan utvecklas for okad miljovanlighet och livslangd gar rapporten igenom olika vegetabiliska oljor, vilka fordelar de har gentemot mineraloljor och vilka egenskaper de har samt pa vilket satt de ar skonsammare mot miljon. HVDC-enheter transformerar hoga spanningar fran vaxelspanning till likspanning for mindre resistiva forluster och darmed lagre energiforluster vilket i sin tur leder till en renare miljo. Teorigenomgangen av transformatorn ligger till grund for utformningen av en laboration for undervisningsbruk, bl.a. i en kurs om elkraftteknik som ges i hogskoleingenjorsprogrammet Elektroteknik pa KTH. / This degree project was carried out on behalf of the unit for Computer and Electrical engineering at the School of Technology and Health, KTH. This study about transformers, their function and uses, the way they’re built, how the core and windings, which are the most important parts of a transformer, are made and what kind of materials are used to make them. Several types of transformers and their functions are described. A crucial part of the study has been to search for different ways to develop transformers to make them environmentally safer and to increase their life-span. As such this work describes different transformer oils, what advantages and disadvantages they have compared to mineral oils, what properties they have and in what way they’re less harmful for the environment. HVDC units transform high voltages from Alternating Current to Direct Current to lessen the resistive losses and energy losses which lead to a cleaner environment. The theory examination of the transformer is the basis for the formation of a lab for educational use, among others in a course about electrical power that’s included in Bachelor of Science in Electrical Engineering at KTH.

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