Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-03-02T14:35:50Z No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-06T19:43:31Z (GMT) No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) / Made available in DSpace on 2017-03-06T19:43:31Z (GMT). No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) Previous issue date: 2009-04-16 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Este trabalho apresenta a proposta de um reator eletrônico ressonante dedicado à realização de testes de funcionalidade básica de lâmpadas de vapor de sódio e de vapor de mercúrio em alta pressão. Os testes são realizados com potência reduzida visando economizar energia elétrica e minimizar o ofuscamento dos operadores. O reator proposto é parte integrante de um sistema de reatores eletrônicos que deve substituir um conjunto de reatores eletromagnéticos utilizados em uma bancada de testes de componentes de iluminação pública. A utilização do conjunto de reatores substitutos propiciará a redução do peso e do volume da bancada, facilitando sua confecção em escala. O trabalho inclui um estudo teórico sobre lâmpadas de descarga de alta intensidade (HID) e sobre o fenômeno da ressonância acústica, que pode acometer estas lâmpadas quando são alimentadas em alta freqüência. O estudo sobre reatores eletrônicos para lâmpadas HID apresentado enfatiza o reator eletrônico série-paralelo ressonante. Este reator é utilizado neste trabalho para a realização dos testes com potência reduzida das lâmpadas de vapor de sódio em alta pressão de 70W e vapor de mercúrio em alta pressão de 125W sem a excitação do fenômeno da ressonância acústica e sem a necessidade de modificação de nenhum parâmetro do circuito. Para isto, foi desenvolvida uma metodologia para que o projeto do circuito ressonante série-paralelo pudesse atender ambas as lâmpadas em operação dimerizada. Apresentam-se ainda resultados experimentais dos testes realizados com o reator implementado. / This work presents a proposal of a resonant electronic ballast intended for the basic functionally testing of high pressure sodium and mercury lamps. The tests are performed with reduced power in order to save energy and to minimize operators’ glare effect. The proposed ballast is part of an electronic system that would replace a number of electromagnetic ballasts used in a lighting components bench test equipment. The use of this electronic system will provide the reduction of the weight and volume of the bench test equipment, favoring its commercial production. Theoretical studies about high intensity discharge lamps and acoustic resonance phenomenon, which can affect those kind of lamps in high frequency operation, are accomplished. The study of electronic ballasts for HID lamps presented emphasizes the series-parallel load resonant ballast. This ballast is used in this work for testing 70W high pressure sodium lamps and 125W high pressure mercury vapour lamps with reduced power, without exciting the acoustic resonance phenomenon and with no need of any circuit parameter modification. For this purpose, it was developed a design methodology of the series-parallel resonant circuit aiming dimmed operation of both lamps. Experimental results of tests performed with the implemented ballast are also included.

This thesis treats concept of autonomous temperature, relative humidity and pressure USB datalogger. Also there is explained datalogger function, hardware design with respect on device consumption and design of chassis. Furthermore, there is described communication protocol for control and reading out data by the PC. Furthermore, there are described firmware drivers for some used components and modules for USB communication, RTC and data compression. Lastly there is described software which is used for datalogger configuration and data read out.

This master’s thesis deals with the draft and design of HID periphery Touchpad. The Kinetis microcontroller produced by NXP, TSI periphery and embedded library NXP Touch are used for the design. The resulting device is connected as USB HID type mouse or trackpad. Hardware part of the project is implemented by whole MCU Kinetis Family on PCBs designed by author, one part also uses evaluation kits NXP Freedom KL25z and KE15z.

Around 19% of global power consumption and around 3% of global oil demand is attributable to lighting. After the first incandescent lamp was invented in 1879, more and more energy efficient lighting devices, such as gas discharge lamps, and light-emitting diodes (LED), have been developed during the last century. It is estimated that over 38% of future global lighting energy demand could be avoided by the use of more efficient lamps and ballasts [1]. High intensity discharge (HID) lamps, one category of gas discharge lamp, have been widely used in both commercial and residential lighting applications due to their merits of high efficacy, long life, compact size and good color rendition [2-4]. However, HID lamps require a well-designed ballast to stabilize the negative VI characteristics. A so-called ignitor is also needed to provide high voltage to initiate the gas discharge. Stringent input harmonic current limits, such as the IEC 61000-3-2 Class C standard, are set for lighting applications. It is well-known that high-frequency electronic ballasts can greatly save energy, improve lamp performance, and reduce the ballast size and weight compared with the conventional magnetic ballast. However, a unique phenomenon called acoustic resonance could occur in HID lamps under high-frequency operation. A low-frequency square wave current driving scheme has proved to be the only effective method to avoid acoustic resonance in HID lamps. A typical electronic HID ballast consist of three stages: power factor correction (PFC), DC/DC power regulation and low-frequency DC/AC inverter. The ignitor is usually integrated in the inverter stage. The three-stage structure results in a large size and high cost, which unfortunately offsets the merit of the HID lamp, especially in low-wattage applications. In order to make HID lamps more attractive in low-wattage and indoor applications, it is critical to reduce the size, weight and cost of HID ballasts. This dissertation is aimed at developing a compact HID with an ultra-compact ballast installed inside the lamp fixture. It is a similar concept to the compact fluorescent lamp (CFL), but it is much more challenging than the CFL. Two steps are explored to achieve high power density of the HID ballast. The first step is to improve the system structure and circuit topology. Instead of a three-stage structure, a two-stage structure is proposed, which consists of a single-stage power factor correction (SSPFC) AC/DC front-end and an unregulated DC/AC inverter/ignitor stage. An SSPFC AC/DC converter is proposed as the front-end. A DCM non-isolated flyback PFC semi-stage and a DCM buck-boost DC/DC semi-stage share the semiconductor switch, driver and PWM controller, so that the component count and cost can be reduced. The proposed SSPFC AC/DC front-end converter can achieve a high power factor, low THD, low bulk capacitor voltage, and the desired power regulation with a simple control circuit. Because the number of high-frequency switches is reduced compared to that of state-of-the-art two-stage HID ballast topologies, the switching frequency can be increased without sacrificing high efficiency, so the passive component size can be reduced. The power density of the whole ballast is increased using this two-stage structure. It results in a 2.5 times power density (6 W/in3) improvement compared to the commercial product (2.4 W/in3). The power density of the converter in discrete fashion usually suffers as a result of poor three-dimensional (3D) volume utilization due to a large component count and the different form factor of different components. In the second step, integration and packaging technologies are explored to further increase the power density. A 3D passive integrated HID ballast is proposed in this dissertation. All power passive components are designed in planar shape with a uniform form factor to fully utilize the three-dimensional space. In addition, electromagnetic integration technologies are applied to achieve structural, functional and processing integration to reduce component volume and labor cost. System partitioning, integration and packaging strategies, and implementation of major power passive integration, including an integrated EMI filter, and an integrated ignitor, will be discussed in the dissertation. The proposed integrated ballast is projected to double the power density of the discrete implementation. By installing the HID ballast inside the lamp fixture, the ambient temperature for the ballast will be much higher than the conventional separately installed ballast, and combined with a reduced size, the thermal condition for the integrated ballast will be much more severe. A thermal simulation model of the integrated ballast is built in the IDEAS simulation tool, and appropriate thermal management methods are investigated using the IDEAS simulation model. Experimental verification of various thermal management methods is provided. Based on the thermal management study, a new integrated ballast with improved thermal design is proposed. / Ph. D.

This master's thesis deals with design electronics for an antenna rotator in two axis. There are designed and implemented drivers for two stepper motors. Was also designed and implemented control panel that allows manual control the rotator and remote control by PC via USB. At the same time created software for control panel and PC application for easy operation.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents a detailed analysis about the interleaved buck converter applied to electronic ballasts to supply high power HID lamps, assuming the input voltage as a PFC stage output. As the output capacitor has a maximum value to be applied in parallel with the lamp, parallel operated converters are a suitable choice because the output current ripple cancellation characteristic. Besides, the output current ripple cannot be greater than 5% of the nominal current to avoid acoustic resonance phenomena. Also, interleaved converters allow magnetic and semiconductors losses reduction. The applied topology was the interleaved buck converter, because its inherent characteritstic of the output as a current source. A generalized model for the IBC operating in CCM was obtained, including inductors and semiconductors losses, besides an analysis to achieve the optimum point of design in terms of efficiency, size and complexity of implementation. To apply the IBC in CCM supplying HID lamps, it is necessary inductors current control, which means to guarantee a current source behavior of the converter. For that, two current control loop were designed, one for each inductor being measured via a shunt resistor located at the circuit input. Also, stability was analyzed based on impedance criterion. Finally, complete electronic ballast was presented, gathering a two-cell IBC, full-bridge inverter, measuring circuits for current and voltage and an external circuit for the correct delay of the IBC MOSFETs gate signals. Obtained experimental results were satisfatory, showing equal current sharing, once warm-up stage and closed-loop implementation were via an 8-bits microcontroller. / Este trabalho apresenta uma análise detalhada do conversor buck intercalado como reator eletrônico aplicado à alimentação de lâmpadas de descarga em alta pressão (HID) de alta potência, assumindo a entrada como a saída de uma etapa de correção de fator de potência (PFC). A característica de diminuição da ondulação da corrente de saída de conversores operando em paralelo é uma grande vantagem, pois o capacitor em paralelo com a lâmpada tem um valor limite a fim de garantir a estabilidade do sistema. Aliada a essa condição, a ondulação de corrente na lâmpada não pode ultrapassar 5% da corrente nominal para garantir que não ocorra o fenômeno da ressonância acústica de forma destrutiva. Além disso, permitem redução de perdas magnéticas e nos semicondutores, além de apresentar diminuição na ondulação da corrente de saída através da defasagem dos sinais de comando dos interruptores, diminuindo o capacitor de saída a ser empregado. Em termos de análise do conversor buck intercalado (IBC), foi obtida uma modelagem generalizada para o conversor operando em modo de condução contínua (CCM) incluindo as perdas nos interruptores, indutores e diodo. Também foi realizada uma análise de ponto ótimo de projeto contemplando tamanho, eficiência e complexidade de implementação. Para a utilização do IBC em CCM na alimentação de lâmpadas HID é necessário o controle de corrente dos indutores, ou seja, garantir que o conversor tenha o comportamento semelhante à uma fonte de corrente. Para tal, foram utilizadas duas malhas de controle de corrente, uma para cada indutor, sendo o sinal de controle medido através de um resistor shunt localizado na entrada do conversor. Ainda, foi apresentada uma análise de estabilidade baseada na relação entre as impedâncias da lâmpada e do conversor, com realimentação em modo corrente. Finalmente, o reator completo foi apresentado, constituído do IBC com duas células, inversor full-bridge, circuito inibidor para defasagem dos sinais de comando do IBC e o circuito de medição das correntes e tensão. Os resultados experimentais obtidos foram satisfatórios, com correntes equilibradas, uma vez que o IBC com malha fechada em ambos os indutores foi implementado com um microcontrolador de 8-bits, com frequência de barramento de 16 MHz.

Wireless communication is increasingly ubiquitous. However, mobility depends intrinsically on battery life. Power can be conserved at the Media Access Control (MAC) layer by intelligently adjusting transmission power level and data rate encoding. WirelessUSB is a low-power, low-latency wireless technology developed by Cypress Semiconductor Corporation for human interface devices such as keyboards and mice. WirelessUSB devices conserve power by employing power-efficient hardware, dynamic power level adjustment and dynamic data rate adjustment. We characterize the effects on power consumption of dynamically adjusting node power using two dynamic power negotiation techniques as well as two reactive techniques. We also characterize the effects of dynamically adjusting data rate using three rate adjustment techniques. We further characterize the effects of collaboratively adjusting both power and data rate. We validate our techniques through simulation and find that such collaboration yields the greatest energy conservation for a wide variety of conditions and usage models.

This thesis describes the design guidelines from two medical teams, electrocardiogram and pulse oximetry using embedded logic circuitry such as FPGA and microcontrollers, digital filters used to filter the signals obtained from analog converters to digital, graphic obtaining the data is displayed in a graphic display GLCD, and has an interface to send data to a PC through a port USB 2 at full speed. The digital filters used are FIR filters, these filters are chosen to be linear and time invariant, developed with 40 coefficients FIR filters, these filters were implemented in the FPGA, use a FPGA that has implemented only 20 multipliers For the implementation we used the VHDL language and algorithmic state machines in order to control the 20 boxes and get the 40 products. Filtered data in the stage of the FPGA, are taken to a microcontroller that is responsible for managing the data, can lead to a graphic display GLCD, and so we can see the signal and obtained values or you can send the data to a PC right through USB port and software right through it can see the graphics on the PC.

This thesis deals with design of numeric keyboard, which can be connected to personal computer or laptop through USB interface. This numeric keyboard can be also configured using application for operating system Windows. Backlight pattern generator is also part of this application. Theoretic part deals with various types of keyboards, switches and closer description of USB interface. Practical part deals with sole design of circuit that detects keystrokes and sends information about active switches through USB, description of used components, description of microcontroller service routine and description of the application for backlight pattern generating. At the end of this thesis are described results of measurements which were made to choose mechanical switches with shortest debounce time and keyboard response to key press.

This work is concerned with development of module for communication with intelligent instalation into houses system. The aim was to familiarize with the products of RF Control of  ELKO EP, s.r.o., USB bus and wireless communication components for the 868 MHz band. And afterwards, in cooperation with the ELKO EP company, to design an electrical scheme and printed circuit board motive of this module. For cooperation with the module and for the system components control an aplication was programmed. The application name is RF-AP USB.