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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.
151

Asynchronní motor se stíněným pólem / Shaded-Pole Induction motor

Žuška, Martin January 2008 (has links)
Single-phase shade-pole motor has easy structure, and i tis chlap. It can be used as a drive of electrical fans, drive of small household appliancesor as a gramophonic motor. Motor is rotating one way only. Direction of roteting is given by positron of shading ring. Motor is not very effective, and i tis not efficient.
152

Způsoby měření otáček a kroutícího momentu v automatizovaných systémech / Speed and Torque Automated Measurement Systems

Vávra, Josef January 2009 (has links)
The objektive of this thesis is acquaint with ways of speed sensing and torque noment sensing in automated systems and apply to chosen instruments to the real laboratory work, witch sould by instrumental for education in laboratory of drives.
153

Výpočet jednofázového asynchronního motoru / Single-Phase Induction Motor Calculation

Volf, Lukáš January 2012 (has links)
This work is in the first chapter deals with the basic properties of single phase and three-phase induction motors. The following describes the procedure for obtaining a starting torque of single-phase asynchronous motor. In the second part of the calculation is carried out single-phase induction motor with a permanently connected capacitor and its control, calculation of output values, the program proposed solution to this calculation in Microsoft Excel 2007 and calculated parameters of the development of methods of calculation were compared with measured, the values supplied by ATAS Náchod.
154

Tvorba simulačního modelu obráběcího stroje pro určení energetické spotřeby / Design of a simulation model of the machine tool for determining the energy consumption

Vespalec, Tomáš January 2015 (has links)
This diploma thesis deals with a design of the simulation model of a CNC machine tool for determining the energy consumption. It describes a design of the mechanical and the electrical model of the CNC machine and a design of the energy consumption algorithm. The result of that thesis is a size of the consummated energy during a machining process.
155

Malé asynchronní motory pro specifické aplikace / Small Induction Motors for Specific Applications

Bárta, Jiří January 2016 (has links)
The aim of this master`s thesis is to introduce the principle of construction of a single-phase shade-pole motor and its utilization in automotive industry. It is very simple motor in its structure. The position of shading ring gives us the direction of rotation. It is used mainly when low efficiency is needed, e. g. to run electrical fans, small household appliancesor. Cheap construction is its undeniable advantage.
156

Optimalizace tvaru drážky asynchronního motoru / Rotor Slot Shape Optimization of an Induction Machine

Szekeres, Vojtech January 2016 (has links)
This thesis is dealing with optimization by using artificial intelligence of an induction machine rotor slot. The one optimized is commonly manufactured induction motor with simple deep bar rotor. Goal is to design an optimization method and achieve the highest possible value of efficiency and power factor of chosen machine. Work contains the parametric model construction in Ansys Maxwell software, the optimization algorithm assembly and its setup for desirable output, and processing of the results.
157

Asynchronní motor s plným rotorem / An induction machine with solid rotor

Fišer, Jan January 2017 (has links)
This master’s thesis is focused on induction motor with solid rotor. The introduction is dedicated to the full analysis of the rotor. Then model of motor with solid rotor was designed in 2D and 3D. Simulations of these models were carried out using the finite elements method. Further in this thesis there are laboratory measurements` results due to the motor`s sample. Based on the results from simulations and measurements rotor modifications have been proposed, which led to improved machine parameters. 2D models have been developed by rotor modifications. These models went through finite elements method`s simulation. In the conclusion of the thesis there are all results from measurements and simulations compared.
158

Emulador de turbina eólica : uma ferramenta para o estudo experimental e computacional /

Oliveira, José Rodrigo de. January 2019 (has links)
Orientador: André Luiz Andreoli / Resumo: As fontes renováveis de energia apresentam-se como solução para problemas relacionados ao aumento da demanda por energia elétrica e crescimento dos níveis de emissão de gás carbônico, uma vez que são não poluentes, limpas e abundantes. Aproveitamentos eólicos se mostram como uma das mais promissoras fontes de energia renovável, e por essa razão as pesquisas envolvendo este tipo de aproveitamento têm despertado grande interesse na comunidade científica. Este trabalho apresenta o desenvolvimento de um emulador de turbina eólica (ETE), uma ferramenta de apoio às investigações experimentais capaz de reproduzir o comportamento mecânico dinâmico de uma turbina eólica através de uma malha de controle digital em configuração de hardware-in-the-loop atuando sobre um acionamento eletrônico de uma máquina de indução Operando como fonte de força motriz, o ETE torna mais fácil a avaliação dinâmica de geradores e seus sistemas de controle associados voltados às aplicações envolvendo energia eólica. A pesquisa apresenta uma revisão bibliográfica sobre o estado da arte, a modelagem e a implementação experimental de um emulador de turbina eólica utilizando um motor de indução trifásico (MIT) acionado por um inversor de frequência. Para isso, é implementado um controle em malha fechada de conjugado e velocidade. Este controle faz com que o acionamento eletromecânico representado pelo MIT e inversor de frequência apresente em seu eixo o comportamento de uma turbina eólica conforme os parâmetros... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
159

Electromagnetical model of an induction motor in COMSOL Multiphysics

Wilow, Viktor January 2014 (has links)
Ansys, Flux or COMSOL are examples of software-tools that can be used to study magnetic noise, caused by magnetic forces in the air-gap, in induction motors. The project team wanted to use COMSOL in this thesis. The electromagnetical domain needs to be coupled to the mechanical domain to complete the study. The air-gap forces, calculated in the electromagnetical model using the Rotating Machinery module, can be exported to the Acoustic-Solid Interaction module in COMSOL to enable the vibro-acoustic analysis. An electromagnetical model of an induction motor is developed in two-dimensions in the finite element method based software-tool COMSOL Multiphysics in this thesis. Simulation results obtained in the frequency domain are compared with results achieved in the software-tool FEMM. Simulation results of the phase inductance, distribution of the flux density and the torque are compared. The simulated torque in COMSOL is validated with the torque derived based on an equivalent lumped model of the induction motor. A time-dependent simulation of the motor is made at 4.7% slip and 1A (peak) supply. The obtained torque is 0.33Nm. The same value is achieved in the frequency study in COMSOL. The corresponding value is 0.003Nm higher in FEMM. The evaluated air-gap forces at 4.7% slip can be used for studying vibro-acoustics in COMSOL. / Ansys, Flux eller COMSOL är exempel på datorprogram som kan användas för att studera magnetiskt brus, orsakad av magnetiska krafter i luftgapet, i induktionsmotorer. Projektgruppen ville använda COMSOL i det här examensarbetet. För att kunna utföra studien måste den elektromagnetiska domänen kopplas till den mekaniska domänen. Luftgapskrafterna, beräknade i den elektromagnetiska modellen genom att använda modulen för roterande maskiner, kan exporteras till modulen Acoustic-Solid Interaction för att möjliggöra den vibro-akustiska analysen. En elektromagnetisk modell av en induktionsmotor är utvecklad i två dimensioner i finita elementmetoden-baserade programvaran COMSOL Multiphysics i det här examensarbetet. Simuleringsresultat från frekvensdomänen jämförs med resultat som uppnås med datorprogramvaran FEMM. Simuleringsresultat för fas-induktansen, fördelningen av flödestätheten och momentet jämförs. Det simulerade momentet i COMSOL valideras med momentet som härleds utifrån induktionsmotorns motsvarande ekvivalenta schema. En tidsberoende motor-simulering genomförs vid 4.7% slip, matad med 1A (topp-värde). Det erhållna momentet är 0.33Nm. Samma värde erhålls i frekvensstudien i COMSOL. Värdet är 0.003Nm högre i FEMM. De beräknade luftgapskrafterna vid 4.7% slip kan användas för att göra en vibroakustisk studie i COMSOL.
160

Inteligentní testovací procedury nízkonapěťových trakčních pohonů s asynchronními motory / Intelligent Test Procedures Low-Tension Traction Drives with Induction Motors

Nesvadba, Martin January 2011 (has links)
This dissertation thesis is focused on the problem of the noise measurement and construction of the noise test station what was also interest of my employer - company Kollmorgen,sr.o. This testing station should be located directly in the assembly line with target of the noise motor s identification. On base of these measured values and implemented intelligent testing procedures, we should be able to identify real root cause of the noise The noise of electrical machines is actual issue. There is a big pressure for low-noise driving system construction created by many end-customers. We can achieve these requirements with 100% quality of all parts of current product, implementation of noise testing station and also with design optimization of the current product. Basic testing procedures of induction motors were showed in first part of this work (chapter 4.1.). These procedures are able to provide good picture of the motor condition. For the motor noise measurements was constructed a workplace including noise box with acoustical absorption up to 30dB what allowed the workplace implementation directly into the motor assembly line. Testing techniques and frequency analysis procedures were implemented sequentially with the target of the test evaluation improvement. After the detailed analyze of the motor noise root causes was performed check of the current motor design with respect of the “noiselessness” motor construction principles. As next step was created the motor prototype with optimized construction with target of the motor noise reduction. This optimized motor was tested and compared with standard motor design.

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