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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.
51

Implementation of a Dual-Active-Bridge Bidirectional Isolated DC to DC Converter in Home Area Network

Lo, Sheng-Chieh 13 September 2012 (has links)
In recent years, smart gird has received much attention, and many researchers have devoted to home area network (HAN) to improve the efficiency of grid. This thesis proposes a bidirectional isolated DC-DC converter (Dual Active Bridge, DAB) with phase shift control to implement the concept of HAN. Li+Fe battery is used as storage device of the converter, and a bidirectional communication between Laboratory Virtual Instrumentation Engineering Workbench (LabVIEW) and Digital Signal Processor (DSP) is realized by CAN-bus. By setting the current command given by LabVIEW system, the converter is able to charge the Li+Fe battery with constant current and constant voltage method as well as discharge the Li+Fe battery with constant current. Operation principle of the converter and the associated loss are presented.
52

Výpočtové modelování tuhosti záběru ozubených kol / Numerical Modelling of the Gear Mesh Stiffness

Gazda, Silvester January 2017 (has links)
This master's thesis deals with the design of FEM model of gear pair with an intention to find out how stiffness changes during meshing. It firstly describes the necessary knowledge needed to analyse the problem, like the geometry of an involute tooth and evaluation of meshing stiffness. Followed by a description of work procedures from the creation of models through settings of mesh, contacts and analysis to evaluating of results.
53

Praktické porovnání přístupů návrhů tlakových nádob v rámci ČSN EN 13445 / Practical comparison of pressure vessels design approaches within ČSN EN 13445

Procházka, Tomáš January 2020 (has links)
This diploma thesis deals with a practical comparison of pressure vessels design approaches within ČSN EN 13445. The thesis aimed to design the device using various approaches described in the European Standard and compare them. For the design was chosen a liquid filter, which works as the first stage of the filtration system in a waste-to-energy plant. In the first part of the thesis is introduced to different routes of design by analysis (DBA), including a description of plasticity conditions and finite element types. These theoretical knowledge are applied in the practical part. The practical part consists of designs of the pressure vessel according to different approaches and methods. The first approach is a design by formulae (DBF), which was done in software Visual Vessel Design. The second approach is DBA. This method of design can be realized according to the European Standard by two routes, either by Method base on the stress categories or so-called Direct Route. Both routes were performed in this work. Stress analyzes were made in programs ANSYS Workbench and NozzlePRO. At the end of the thesis, there is a comparison of used approaches and the resulting values of the design.
54

Návrh testovacího přípravku piezoelektrických vlastností PVDF vrstvy / Design of tester of piezoelectric PVDF layers

Sijková, Simona January 2020 (has links)
The diploma thesis deals with a design of a tester device, a selection and verification of a suitable method for comparing the piezoelectric properties of tested PVDF samples. In the introduction, a basic overview of the theory is important to understand the issue and the various branches of use of PVDF in the field of energy harvesting. The tester device includes a unimorph piezoelectric cantilever beam with tip mass, whose properties are described by three models: a model with N degrees of freedom reduced to one degree of freedom (NDOF), a single degree of freedom model (SDOF), both created in Matlab and a model for verifying results in FEM ANSYS Workbench program. The voltage time response and the voltage frequency response of the models is compared with each other. For two different PVDF samples, the voltage response to harmonic excitation is measured using a tester device, and the piezoelectric properties of one of them are determined using the NDOF and SDOF models.
55

Využití počítačové grafiky v silnoproudé elektrotechnice / The utilization of computer graphic in power electrical engineering

Bzduch, Pavel January 2008 (has links)
The aim of this work is to describe news in Autodesk Inventor Professional 2008. In second part of the work there are described the possibilities of technical drawing in Autodesk Inventor. In third part there is mentioned basic information about ANSYS Workbench. There is thermal simulation of asynchronous motor too.
56

Využití programu ANSYS Workbench v silnoproudé elektrotechnice / Utilization of ANSYS Workbench program at power electrical engineering

Partl, Tomáš January 2009 (has links)
In its first part this Master´s thesis describes creation of electronic database design in Raster Design 2009 program as an effective form of storage only for paper documentation. The second part of my thesis provides calculation of primary and secondary winding of current instrument transformer of over-current conduit through the winding and influence on other parts of transformer i.e. error of transformer or increasing magnetic induction core and others. The last third part is focusing on usage of ANSYS Workbench in power electrical engineering. The thesis shows specific example of warming of current instrument transformer (thermal analysis) and comparing the results with theoretical (calculated) values.
57

Studie srovnání vlastností pouzder QFN a BGA / Study of BGA and QFN package properties

Skácel, Josef January 2015 (has links)
This work deals with the issue of packaging and heat transfer. Especially this work focused on QFN and BGA packages. Nowadays most sophisticated conventional solution. First part deals with analysis of the current status of packages. Next part is analyze the issue of heat transfer in electronic systems. The following section is an experimental dealing with simulation in ANSYS Workbench and validation of these simulations by designed test structures. At the end is evaluated properties and behavior of these packages.
58

Návrh konstrukčního řešení autoklávu / Design of autoclave

Poduška, Libor January 2016 (has links)
Master thesis deals with general basic design od autoclaves. It deals with the design of an optimal design solution autoclave to set parameters with the design requirement of hermetic doors for loading the workpiece. This solution is analyzed regard to stable pressure vessels. The whole design is processed in parametric SolidWorks software with which they are executed and initial stress analysis of individual designs. Final strength FEM analysis is performed using Ansys. Some proposals are technical-economic evaluation.
59

Působení sekundárních elektrických přístrojů na oteplení skříně rozváděče. / Influece of secondary apparatuses on assembly box heating

Dobiáš, Pavel January 2016 (has links)
This master's thesis deals with the temperature-rise of selected parts of the low-voltage switchgear. The theoretical part describes the physical principles and the basic mechanisms of heat transfer. The next part describes the possible effect of elevated temperature on the device inside the switchgear. The master's thesis is awarded by ABB Ltd., so another part is dedicated to MNS switchgear. The following part describes the permitted limit of temperature-rise of switchgear in accordance with IEC 61439-1. In the practical part is a calculation temperature-rise of selected part of switchgear based on IEC 60890. Model in SOLIDWORKS Flow Simulation was created for the same part of the switchgear and thermal analysis was performed. The values of allowable temperature rise of individual parts are compared with the results obtained by calculations and simulations. In the last part is verified the possibility of calculating the temperature-rise in the EPLAN software.
60

Jeřáb radiální portálový / Radial gantry crane

Dias, Aleš January 2016 (has links)
The aim of my thesis is a conceptual design radial gantry crane including the important strength calculations according to the standards and examinations by means of ANSYS Workbench. The lifting capacity is 1500 kg, the length of the boom is 12 000 mm and the height of lifting is 3600mm. The crane is designed as fully revolving and the angle turning is 360°. The work also includes the selection of a suitable lifting gear from the manufacturer´s catalogue including the accessories casters, all important components and also FEM construction analysis.

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