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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.
201

Spínané zdroje ve vozidlech elektrické trakce / Switching source in electric tractions vehicle

Škunda, Michal January 2010 (has links)
The first part of this work describes the design and implementation of switch-mode power supply for control circuits for 12/2x24V 4.5A fuel cells. The introduction picks the issue of power sources in electromobiles and final design and implementation of switching power suply. The next part deals with the issues of fast-charger and generators for power transistors. It describes the structure of DC converter and control and protectin circuits of quick-charger. In the end this work describes selected driver circuits and charge tests on fast-charger as evidenced by measurements.
202

Kompaktní měnič pro stejnosměrný motor / Compact inverter for DC motor

Kvapil, Martin January 2013 (has links)
This master thesis deals project and realization of universal transistor converter for power electronics course. For this converter was at the same time designed control circuit and drive circuit. Next part is about the design of compact converter for DC. This converter is controlled by a microprocessor Freescale.
203

Zdroj pro vysoce svítivé bílé LED / Driver for ultra-bright white LED

Heralecký, Lukáš January 2015 (has links)
The aim of this thesis is to study the possibilities of controlling high-brightness white LEDs using circuits operating at high voltages. The job itself is a division of existing light sources and mainly focus on semiconductor technology LED. The following describes the voltage of DC / DC and AC / DC. The work contains a description of the three high-voltage inverters are designed for power LEDs. Finally, it created a draft scheme of the PCB. As a control circuit is chosen ATMEGA 162 microcontroller from Atmel and source for LED diode is formed HV9910 and HV9861 circuits.
204

Mathematische Modellbildung, Regelung, Simulation und Praktische Umsetzung eines bidirektionalen DC-DC-Umrichters zur Pufferung von Solaranlagen

Wolfram, Heiko 06 July 2005 (has links)
Begleitend zur Diplomarbeit von Markus Armann: "Untersuchung des Einsatzes von Doppelschichtkondensatoren zur Pufferung der Auswirkungen kurzzeitiger Änderungen der Einstrahlungsintensität in Photovoltaikanlagen", 4/2001.
205

A Modified Multiphase Boost Converter with Reduced Input Current Ripple: Split Inductance and Capacitance Configuration

Hay, Zoe M. 01 June 2018 (has links)
This thesis presents the simulation, design, and hardware implementation of a modified multiphase boost converter. Converter design must consider noise imposed on input and output nodes which connect to and influence the operation of other devices. Excessive noise introduces EMI which can damage sensitive circuits or impede their operation. High ripple current degrades battery lifetime and reduces operating efficiency in connected systems such as PV arrays. Converters with high ripple current also experience greater peak conduction loss and require larger components. A two-phase implementation of a modified boost converter demonstrates the input current filtering benefits of the modified topology with increased power capacity. In a 12V to 19V 95W design, the modified multiphase design exhibits a reduced input current ripple of 1.103% compared to the 9.096% of the standard multiphase design while imposing minimal detriment to overall converter efficiency. The modified topology uses two inductors and one feedback capacitance per phase. Larger value inductors generally exhibit lower current ratings as well as larger size. The split inductance of the modified multiphase topology can be designed for occupation of less total volume than the single inductance of the standard multiphase topology.
206

Monitoring for Reliable and Secure Power Management Integrated Circuits via Built-In Self-Test

January 2019 (has links)
abstract: Power management circuits are employed in most electronic integrated systems, including applications for automotive, IoT, and smart wearables. Oftentimes, these power management circuits become a single point of system failure, and since they are present in most modern electronic devices, they become a target for hardware security attacks. Digital circuits are typically more prone to security attacks compared to analog circuits, but malfunctions in digital circuitry can affect the analog performance/parameters of power management circuits. This research studies the effect that these hacks will have on the analog performance of power circuits, specifically linear and switching power regulators/converters. Apart from security attacks, these circuits suffer from performance degradations due to temperature, aging, and load stress. Power management circuits usually consist of regulators or converters that regulate the load’s voltage supply by employing a feedback loop, and the stability of the feedback loop is a critical parameter in the system design. Oftentimes, the passive components employed in these circuits shift in value over varying conditions and may cause instability within the power converter. Therefore, variations in the passive components, as well as malicious hardware security attacks, can degrade regulator performance and affect the system’s stability. The traditional ways of detecting phase margin, which indicates system stability, employ techniques that require the converter to be in open loop, and hence can’t be used while the system is deployed in-the-field under normal operation. Aging of components and security attacks may occur after the power management systems have completed post-production test and have been deployed, and they may not cause catastrophic failure of the system, hence making them difficult to detect. These two issues of component variations and security attacks can be detected during normal operation over the product lifetime, if the frequency response of the power converter can be monitored in-situ and in-field. This work presents a method to monitor the phase margin (stability) of a power converter without affecting its normal mode of operation by injecting a white noise/ pseudo random binary sequence (PRBS). Furthermore, this work investigates the analog performance parameters, including phase margin, that are affected by various digital hacks on the control circuitry associated with power converters. A case study of potential hardware attacks is completed for a linear low-dropout regulator (LDO). / Dissertation/Thesis / Masters Thesis Electrical Engineering 2019
207

DC-DC power converters with multiple outputs

Sabbarapu, Bharath Kumar 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This study presents a novel converter configuration that is related to the area DC-DC power converters. To begin with, a brief introduction is given by stating the importance of power electronics. Different types of converters, their operating principles and several new topologies that are being proposed over the years, to suit a particular application with specific advantages are listed in detail. In addition, pro- cedure for performing small signal analysis, which is one among the several averaging techniques is summarized in the first chapter. In the second chapter, small signal modeling is carried out on the single input dual output DC-DC buck converter. This analysis is performed to get a clear un- derstanding on the dynamics of this novel configuration. Routh stability criterion is also applied on this converter topology to determine the limiting conditions for operating the converter in its stability. Third chapter proposes the single input multiple output DC-DC synchronous buck converter. It’s operation, implementation and design are studied in detail. In further, small signal analysis is performed on this topology to determine the transfer function. In the following chapter, results obtained on comparison of a losses between the conventional and traditional topologies are presented in detail. In addition, results achieved during the analysis performed in the previous chapter are displayed. In the end, advantages and its highlights of this novel configuration proposed in this study is summarized. Future course of actions to be done, in bringing this configuration in to practice are discussed as well.
208

Design and Simulation of Boost DC - DC Pulse Width Modulator (PWM) Feed-Forward Control Converter

Franklin, Calenia L. 05 August 2020 (has links)
No description available.
209

The Development of an Electric Tricycle and Buck-Topology-Based Battery Pack Charger

Taschner, Matthew John 15 December 2011 (has links)
No description available.
210

Adaptive Automotive Lighting Systems

Haeberlin, Marc W 01 June 2015 (has links) (PDF)
Over the past few years, the use of LEDs within the automotive and avionic industries has increased due to their high efficiency, durability and wide range of light brightness. As the use of LEDs within these industries grows, a need for reliable, high performance drivers becomes more relevant. Companies are implementing LEDs for applications involving adaptive lighting or simple dimming features. This thesis shows implementation of various non-isolated analog converters integrated with digital dimmers to achieve these adaptive lighting systems. Adaptive lighting systems involve reading an input from an external source (brake pedal or steering wheel) and changing the brightness and/or pattern of the brake/headlights to convey more information to the driver and their surroundings. The analog converters will implement Linear Technology’s LED driver IC’s, while the digital dimmers comprise of microcontrollers and discrete components. The design, simulation, and hardware verification will showcase the abilities of these analog converters. Results will demonstrate the proposed applications for both adaptive front and brake lighting.

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