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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.
331

Svítidla a aplikace s Power LED zdroji / Luminaires and Applications with Power LEDs

Vaňko, Adam January 2011 (has links)
Progress in development of modern LEDs, their long lifetime and high luminous efficacy predetermine them for usage in lighting systems. This master's thesis examines possibilities of application of LEDs in luminaires, parameters of diodes and problems, which can appear in construction of luminaire with LED lighting source. In the practical part of this thesis a luminaire is designed, capable of illuminating traffic signs, vertical surfaces, billboards and fasades. By standards required parameters of a lighting system and adaptability of application must be considered in complex predesign. Simulations of lighting scene, created in special computer software, measurements of optical point’s parameters and construction of real luminaire model using high quality CREE LEDs, are included in analysis of the problem. Parameters of the luminaire were proved by measurements of product’s attributes at light laboratory. There are also some suggestions for improvement and further development of the product.
332

Spínaný rezonanční zdroj / Switched resonant power supply

Štaud, Stanislav January 2011 (has links)
This thesis deals with desing of serial resonant converter with regulation output voltage in full bridge configuration like alternative power switching converter with pulse width modulation. The thesis includes analysis of serial resonant converter, desing power transformer, driving circuits. The thesis concludes with the functional converter and complete technical documentation.
333

Regulovatelný zdroj napájený a řízený pomocí USB / Controllable source supplied and controlled via USB

Sedláček, Michal January 2013 (has links)
Master thesis deals with design controllable switching power source. Device is supplied and controlled via USB bus of PC. The required output parameters are specified by user in a computer application. The teoretical part includes method of USB communication and introduction to switching power sources with focus on a Sepic topologii. The practical part describe individual circuit solution which contains of a complete device. Is analyzed in detail the proposal Sepic converter circuit and controling by microcontroller. The work also includes the design of microcontroller and computer applications. The result of this thesis is a functional device on which is the performed measurement.
334

IR teploměr s automatickou korekcí emisivity / IR thermometer with automatic emissivity correction

Dobesch, Aleš January 2013 (has links)
Diploma thesis deals with basic physical quantities and laws relating to non-contact temperature measurement and emissivity determination of solids. It describes the design and implementation of the IR (Infra-Red) thermometer often missed with automatic emissivity correction. The first chapter explains the concept of temperature and basic principles of temperature measuring . The second chapter focuses on the history and theory of non-contact temperature measurement. Gradually are explained the concepts related to non-contact temperature measurement and the problem of determining the emissivity of the body. Next third chapter describes the proposed hardware solution of IR thermometer. The fourth chapter describes a software written for the IR thermometer. The fifth and last chapter summarizes the findings and knowledge from the implementation of non-contact thermometer and measuring emissivity.
335

Systém automatického řízení technologického zařízení / Automatic control system of technology facility

Brabec, Luboš January 2013 (has links)
This bachelor's thesis deals with problematics of technological procedures and techniques for modification of microelectrodes with nanostructures. Furthermore, it describes a device needed for automated production of nanosensors, their properties and communication with computer. These devices communicate through RS-232 and USB interfaces.
336

Digitálně řízený audio zesilovač ve třídě D s dálkovým ovládáním / D class audio-amplifier with digital and remote control

Petrgál, Filip January 2014 (has links)
The contents of this thesis is design of audio power amplifier in Class D with fully digital control and remote control and is divided into two parts . The first part is devoted to the basic principles and theory of key elements of the entire amplifier. The second part consists of a complete description of the design and construction of a power amplifier, digital control with remote control, a spectrum analyzer, equalizer, preamp VU meters and complete power supply. Each proposal contains a detailed analysis of the solutions supported by simulations and software. For individual parts have been completely measured p arameters.
337

Užití výkonových měničů ve zdrojích vysokého napětí / Usage of High Power Inverters in High Voltage Sources

Zemánek, Miroslav January 2009 (has links)
This work is concerned with power inverters for alternate high voltage power sources. The theoretical part describes the topology of inverters that can be used in alternate power sources. A model of voltage transformer is described in details to better understand the parasitic effects that are inevitably present in high voltage power sources and, therefore, have to be taken into consideration at the design of high voltage power sources. The work is oriented to problems of alternate high voltage power sources for ozone generators. This is the reason, why the theoretical and, partially, also the experimental part deal with the properties of ozone and its use. The experimental part solves high voltage inverter with capacitive load that is formed by discharge element of an ozone generator. Designed inverter is able to feed the capacitive load with high voltage at very short periods of time from several microseconds up to tens of nanoseconds. In comparison with the length of voltage pulses in common ozone generators, this pulses are more than 100-time shorter. This has a positive effect to silent discharge characteristics.
338

Spínané zdroje velkých výkonů - paralelní řazení zdrojů / High power switch-mode supplies - parallel connection

Kadlec, Josef January 2016 (has links)
This doctoral thesis deals with the issue of high power switched-mode power supplies that are designed as modular systems. The thesis describes series, parallel and series-parallel possibility of connected converters. System can achieve extremely high output current for converters connected in parallel. For converters connected in series, the system can achieve extremely high output voltage. The main goal of this thesis is to develop so-called reconfigurable modular system. It is a system that can change converters connection of serial, parallel or series-parallel connection - during its operation. This option to change converters connection significantly extends the control range of output voltage and output current of the whole system. For all these mentioned variants of the modular system there are described and simulated suitable control schemes. The issue of interleaved PWM is described in the thesis. Output voltage ripple and current ripple equations were derived for each converters connection. These equations, which were derived either for systems with interleaved PWM or for systems without of phase shifted PWM, are also proved by simulations. Design of reconfigurable modular system with power of 9.6 kW that contains four converters was introduced in this thesis. Converters use modern transistors and diodes of SiC material. The proposed reconfigurable modular system was successfully manufactured. The measurement results are also shown in the work.
339

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.
340

Měnič pro umělou síť 230 V napájený z fotovoltaických panelů / 230 V inverter for isolated mains supplied from solar cells

Michálek, Pavel January 2016 (has links)
In this thesis is presented detail design of power part of DC/DC converter and output inverter. This device will serve for creating an artificial network in a family house where it will be used for supplying selected household appliances which are designed for use in AC network. The converter will be supplied with DC voltage. This tension will be obtained from a system of photovoltaic panels. The output voltage will have alternate character and it will be close to the network voltage 230 V/50 Hz. In the introductory part of thesis are discussed possible topologies of converters and output inverters. Subsequently are designed individual parts of supply inverter. In the final part there are shown waveforms of important values and is given a thesis evaluation.

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