Electrical and Electronics Commons^™

Implementation Of A Three-Port Solar Converter With A Battery Energy Storage System, Maison Christopher Phipps

Graduate Theses and Dissertations

The increasing deployment of distributed solar and energy storage systems has created the need for integrated power converters that can efficiently manage photovoltaic (PV) generation, battery energy storage, and grid-tied AC output. This thesis presents the implementation and validation of a 5kW non-isolated Three-Port Converter (TPC) adapted for residential solar applications. The converter consolidates three power stage into a high-frequency, compact architecture: a unidirectional boost converter for PV input, a bidirectional interleaved buck-boost converter for battery energy storage, and a configurable DC/AC inverter for 120Vac single-phase output. The system is controlled using a central controller implemented on a TI C2000™ …

Optical Characterization Of Ge And Gesn Grown In Aspect Ratio Trapping Structures For Enhanced Emitter Performance, Abdulla Said Ali

Graduate Theses and Dissertations

Silicon (Si) began dominating the electronics industry since 1960s, the dominance came due to its affordability and well developed fabrication processes. But when it comes to light emitting devices and photonics devices in general, the indirect bandgap of Si has caused many scientists to search for alternative semiconductor materials that can deliver better light emission, materials that can also improve wavelengths detection which is also very limited when it comes to Si, reduce losses and greater light amplification, all this while still being affordable. Despite these limitations, Si has been widely used in Complementary Metal Oxide Semiconductor (CMOS) manufacturing and …

Series Resonant Converters With Medium Voltage Sic Mosfets For Electric Aircraft Applications, Xinyuan Du

Graduate Theses and Dissertations

To develop high-performance high- power-density MV power converters, the emerging silicon carbide (SiC) devices are more attractive than their silicon (Si) counterparts, since the fast switch frequency brought by the SiC can effectively reduce the volume and weight of the filter components and thus increase the converter power density. From the converter topology perspective, with the MV dc distribution, the single stage isolated dc/dc converter are suitable for next-generation electric aircraft system due to soft switching and high power density. In this work, comprehensive static and dynamic characterizations were conducted for the latest 6.5 kV silicon carbide (SiC) MOSFETs from …

Design And Validation Of A High-Frequency Multi-Output Dc-Dc Converter For Radar Power Applications, Tory Sutton

Graduate Theses and Dissertations

Modern radar systems and advanced electronics demand compact, efficient, and reliable power solutions capable of delivering multiple tightly regulated voltage rails under strict size, weight, power, and reliability (SWaP-R) constraints. This thesis presents the design, implementation, and validation of a high-frequency (460 kHz – 1 MHz), multi-output DC-DC converter for a mission?critical radar platform, addressing both integration and performance requirements. The first implementation, an isolated modular converter (IMC), utilizes isolated silicon?based DC-DC modules to deliver twelve isolated voltage outputs from a single input. This approach provided robust electrical isolation, simplified system integration, and minimized design risk, making it well-suited for …

Synthesis Of Nanoparticles And Their Applications In Power Module Packaging And Organic Electronics, Xinsong Zhang

Graduate Theses and Dissertations

Nanoparticles can greatly change the properties of regular materials due to their special structures. In this research nanoparticles, such as silver nanowires, silver nanospheres and expanded graphite, are used in interconnection materials for power module packaging, and in conductive films for organic electronics. Silver nanowires synthesized by polyol synthesis, are used as fillers in micron silver paste. The electrical and mechanical properties of the sintered hybrid silver paste are investigated and compared with those of micron silver paste. The composites of silver nanospheres and expanded graphite are mixed with PEDOT:PSS solutions in 5 different weight ratio. The electrical and optical …

Ω-Shaped Rogowski Coil Current Sensor Optimization Design In Power Electronics Applications, Xia Du

Graduate Theses and Dissertations

Accurate switching current measurement plays a pivotal role in characterization of power devices, overcurrent protection, and real-time control of system-level operations in power electronics applications. However, the ongoing revolution in power electronics, driven by the emergence of wide bandgap power devices operating at megahertz (MHz) switching frequencies, introduces challenges for current sensor design. The urgent issue now is the need to increase current sensor bandwidth significantly to adeptly capture the rapid switching speed current. Additionally, the trend towards high power density and compact power converters in various applications demands current sensors that are not only compact and nonintrusive but can …

Hierarchical Power Converter Physical Design, Tristan Mark Evans

Graduate Theses and Dissertations

The field of power electronics is undergoing rapid advancement that is driven by the need for further electrification in all aspects of power generation and transmission, transportation, and consumer goods. Recent advances in wide bandgap (WBG) semiconductor technologies continue to push their adoption in systems with higher power densities and conversion efficiencies. However, the way in which the components of these systems are designed has not kept pace with the rapidly evolving landscape of their applications and often requires costly, manual design iteration. Therefore, new methods are needed to improve this design process. Packaging of power devices is a critical …

High Performance Silicon Carbide Based Converters For Powertrain Electrification, Nan Lin

Graduate Theses and Dissertations

With the increasing concern towards environment protection, electric vehicles (EVs) and hybrid electric vehicles (HEVs) have become popular in recent years. They not only help reduce carbon emissions, but also come with other benefits such higher efficiency and better user experience. Many countries and vehicle manufactures have made their plans to keep up with this trend in vehicle electrification. Powertrain is an assembly of components in a vehicle that pushes it forward. As for EVs and HEVs, their powertrains are composed of one or more power electronics converters, which are significant to the system. Silicon carbide MOSFETs have shown superior …

Ism-Band Energy Harvesting Wireless Sensor Node, Fnu Naveed

Graduate Theses and Dissertations

In recent years, the interest in remote wireless sensor networks has grown significantly, particularly with the rapid advancements in Internet of Things (IoT) technology. These networks find diverse applications, from inventory tracking to environmental monitoring. In remote areas where grid access is unavailable, wireless sensors are commonly powered by batteries, which imposes a constraint on their lifespan. However, with the emergence of wireless energy harvesting technologies, there is a transformative potential in addressing the power challenges faced by these sensors. By harnessing energy from the surrounding environment, such as solar, thermal, vibrational, or RF sources, these sensors can potentially operate …

Chip- And System-Level Reliability On Sic-Based Power Modules, Pengyu Lai

Graduate Theses and Dissertations

The blocking voltage, switching frequency and temperature tolerance of power devices have been greatly improved due to the revolution of wide bandgap (WBG) materials, such as silicon carbide (SiC) and gallium nitride (GaN). Owing to the development of SiC-based power devices, the power rating, operating voltage, and power density of power modules have been significantly improved. However, the reliability of SiC-based power modules has not been fully explored yet. Thus, this dissertation focuses on the chip- and system-level reliability on SiC-based power modules. For chip-level reliability, this work focuses on on-chip SiC ESD protection devices for SiC-based integrated circuits (ICs). …

Multiple Output Power Supply Using Toroidal Transformers For Medium Voltage Active Gate Drivers, Samhitha Venkata Machireddy

Graduate Theses and Dissertations

When operating in high power applications, power devices dissipate tens or hundreds of watts of power in the form of heat. The ability of the power devices to withstand power and dissipation of heat across the power devices becomes a prominent requirement in designing the power converter. This challenge demands a power converter design to be more effective and consistent which factors in size, cost, weight, power density and reliability. This study aims to propose a gate driver isolated power supply design that can be used in medium voltage applications (e.g., up to 10 kV) while respecting the principle of …

Stream Processor Development Using Multi-Threshold Null Convention Logic Asynchronous Design Methodology, Wassim Khalil

Graduate Theses and Dissertations

Decreasing transistor feature size has led to an increase in the number of transistors in integrated circuits (IC), allowing for the implementation of more complex logic. However, such logic also requires more complex clock tree synthesis (CTS) to avoid timing violations as the clock must reach many more gates over larger areas. Thus, timing analysis requires significantly more computing power and designer involvement than in the past. For these reasons, IC designers have been pushed to nix conventional synchronous (SYNC) architecture and explore novel methodologies such as asynchronous, self-timed architecture. This dissertation evaluates the nominal active energy, voltage-scaled active energy, …

Analysis Of An Isolated Bidirectional Ćuk Converter, Yeny Hau Chen

Graduate Theses and Dissertations

The objective of this thesis is to perform an analysis of the isolated bidirectional Ćuk dc-dc converter topology and demonstrate the advantages and operation of this configuration through simulations using MATLAB/SimulinkTM and measurements collected from a 1.5-kW prototype tested at the Engineering Research Center (ENRC) laboratory of the University of Arkansas. The idea of integrating an active-clamp snubber circuit on each side of the converter, proposed by Dr. Sudip Mazumder from the University of Illinois, Chicago, limits the additional voltage stresses on the components due to the energy from the transformer’s leakage inductance. This is studied in this thesis to …

Electrical Modeling For Dynamic Performance Prediction And Optimization Of Mcpms Layout, Quang Minh Le

Graduate Theses and Dissertations

In recent years, the fast development of Multichip Power Modules (MCPM) packaging and Wide Bandgap (WBG) technology has enabled higher voltage and current ratings, better thermal performance, lower parasitic parameters, and higher mechanical reliability. However, the design of the MCPM layout is a multidisciplinary problem leading to many time-consuming analyses and tedious design processes. Because of these challenges, the design automation tool for MCPM layout has become an emerging research area and gained much attention from the power electronics community. The two critical objectives of a design automation tool for MCPM layout are fast and accurate models for design insights …

Hybrid Multilevel Converters With Internal Cascaded/Paralleled Structures For Mv Electric Aircraft Applications, Fei Diao

Graduate Theses and Dissertations

Using on-board medium voltage (MV) dc distribution system has been a megatrend for next-generation electric aircraft systems due to its ability to enable a significant system mass reduction. In addition, it makes electric propulsion more feasible using MV power electronic converters. To develop high-performance high-density MV power converters, the emerging silicon carbide (SiC) devices are more attractive than their silicon (Si) counterparts, since the fast switch frequency brought by the SiC can effectively reduce the volume and weight of the filter components and thus increase the converter power density. From the converter topology perspective, with the MV dc distribution, the …

Evaluation Of Single Phase Smart Pv Inverter Functions In Unbalanced Residential Distribution Systems, Darren Symonette

Graduate Theses and Dissertations

In the United States, smart PV inverters integrated with residential distribution systems are becoming a more common occurrence. With integration of smart PV inverters, power utilities are experiencing an increase of number of operations with regards to switched capacitor banks, voltage regulators and on load tap changers. These increases can lead to excess wear and tear on the devices causing power utilities to perform unwanted replacement and maintenance. However, smart PV inverters when controlled under specific functions can enable these inverters to provide reactive power and voltage control which in turn lowers the number of operations for switched capacitor banks, …

Controller Platform Design And Demonstration For An Electric Aircraft Propulsion Driv, Rosten Sweeting

Graduate Theses and Dissertations

With the growth in the aerospace industry there has been a trend to optimize the performance of an aircraft by reducing fuel consumption and operational cost. Recent advancements in the field of power electronics have pushed towards the concepts of hybrid electric aircraft also known as more electrical aircrafts. In this work, a custom controller board for an electric aircraft propulsion drive was designed to drive a permanent magnet synchronous motor. Design of the controller board required knowledge of the topology selection and power module selections. Simulations of the system were performed using MATLAB/Simulink to analyze the overall performance of …

Study Of Thin Gan/Ingan/Gan Double Graded Structures For Future Photovoltaic Application, Mirsaeid Sarollahi

Graduate Theses and Dissertations

Indium gallium nitride (In_x Ga_(1-x) N) materials have displayed great potential for photovoltaic and optoelectronic devices due to their optical and electrical properties. Properties such as direct bandgap, strong bandgap absorption, thermal stability and high radiation resistance qualify them as great materials for photovoltaic devices. The tunable bandgap which absorbs the whole solar spectrum is the most significant feature which became attractive for scientists. The bandgap for these materials varies from 0.7 eV for InN to 3.4 eV for GaN covering from infrared to ultraviolet. In_x Ga_(1-x) N wurtzite crystal is grown on GaN buffer layer by Molecular Beam Epitaxy …

High Power Density And High Efficiency Converter Topologies For Renewable Energy Conversion And Ev Applications, Dereje Lemma Woldegiorgis

Graduate Theses and Dissertations

This dissertation work presents two novel converter topologies (a three-level ANPC inverter utilizing hybrid Si/SiC switches and an Asymmetric Alternate Arm Converter (AAAC) topology) that are suitable for high efficiency and high-power density energy conversion systems. The operation principle, modulation, and control strategy of these newly introduced converter topologies are presented in detail supported by simulation and experimental results. A thorough design optimization of these converter topologies (Si/SiC current rating ratio optimization and gate control strategies for the three-level ANPC inverter topology and component sizing for the asymmetric alternate arm converter topology) are also presented.

Performance comparison of the proposed …

Analysis And Optimization Of The Two-Phase Series Capacitor Buck Dc-Dc Converter, Salahaldein Ali Aboajila Ahmed

Graduate Theses and Dissertations

Current sharing schemes for conventional multi-phase converters are based on sensing each phase current to deliver the current information to their controllers. In conventional buck converters, this fact may require a preset current sharing ratio at the expense of efficiency, which eventually requires a larger sensing circuit to achieve the sensing accuracy of each phase. Introducing the concept of automatic current sharing is one of the solutions to tackle this issue. Automatic current sharing (Current Sharing Mechanism CSM) is an advanced way to distribute heat generation in multi-phase switching topologies at full load. A two-phase series capacitor buck converter (2-pscB) …

Photoassisted Nanoscale Memory Resistors, Amir Shariffar

Graduate Theses and Dissertations

Memristors or memory resistors are promising two-terminal devices, which have the potential to revolutionize current electronic memory technologies. Memristors have been extensively investigated and reported to be practical devices, although they still suffer from poor stability, low retention time, and laborious fabrication processes.

The primary aim of this project was to achieve a device structure of quantum dots or thin films to address a fundamental challenge of unstable resistive switching behavior in memristors. Moreover, we aimed to investigate the effects of light illumination in terms of intensity and wavelength on the performance of the fabricated memristor. The parameters such as …

Sigesn Light-Emitting Devices: From Optical To Electrical Injection, Yiyin Zhou

Graduate Theses and Dissertations

Si photonics is a fast-developing technology that impacts many applications such as data centers, 5G, Lidar, and biological/chemical sensing. One of the merits of Si photonics is to integrate electronic and photonic components on a single chip to form a complex functional system that features compact, low-cost, high-performance, and reliability. Among all building blocks, the monolithic integration of lasers on Si encountered substantial challenges. Si and Ge, conventional epitaxial material on Si, are incompetent for light emission due to the indirect bandgap. The current solution compromises the hybrid integration of III-V lasers, which requires growing on separate smaller size substrates …

Interplay Between The Lattice And Spin Degrees Of Freedom In Magnetoelectric And Magnetic Materials, Temuujin Bayaraa

Graduate Theses and Dissertations

This dissertation contains several investigations on the cross-coupling between structural and spin degrees of freedom in multiferroic and ferrimagnetic compounds by means of first-principles calculations and ab-initio-based Monte-Carlo simulations. We start with the reviews of magnetoelectricity, ferrimagnetism, strain engineering, followed by a brief introduction to first-principles computational methods, magnetic effective Hamiltonians, and other techniques that are utilized here. The results section of the dissertation can be divided into two parts. The first half focuses on magnetoelectric effects arising from different sources, while the second half is about the ferrimagnetic nature of materials. In the first part, we examine the epitaxial …

A Double-Sided Stack Low-Inductance Wire-Bondless Sic Power Module With A Ceramic Interposer, Si Huang

Graduate Theses and Dissertations

The objective of this dissertation research is to develop a novel three-dimensional (3-D) wire bondless power module package for silicon carbide (SiC) power devices to achieve a low parasitic inductance and an improved thermal performance. A half-bridge module consisting of 900-V SiC MOSFETs is realized to minimize stray parasitic inductance as well as to provide both vertical and horizontal cooling paths to maximize heat dissipation. The proposed 3-D power module package was designed, simulated, fabricated and tested. In this module, low temperature co-fired ceramic (LTCC) substrate with vias is utilized as an interposer of which both top and bottom sides …

Computational Modeling Of Black Phosphorus Terahertz Photoconductive Antennas Using Comsol Multiphysics With Experimental Comparison Against A Commercial Lt-Gaas Emitter, Jose Isaac Santos Batista

Graduate Theses and Dissertations

This thesis presents computational models of terahertz (THz) photoconductive antenna (PCA) emitter using COMSOL Multiphysics commercial package. A comparison of the computer simulated radiated THz signal against that of an experimentally measured signal of commercial reference LT-GaAs emitter is presented. The two-dimensional model (2D) aimed at calculating the photoconductivity of a black phosphorus (BP) PCA at two laser wavelengths of 780 nm and 1560 nm. The 2D model was applied to the BP PCA emitter and the LT-GaAs devices to compare their simulated performance in terms of the photocurrent and radiated THz signal pulse. The results showed better performance of …

Reference Design Of An Online Emulation And Hot-Patching Approach For Power Electronic Controller Validation, Estefano Soria Pearson

Graduate Theses and Dissertations

This thesis aims to develop a reference design of an online security system approach embedded in a power electronic controller for cybersecurity purposes. Cybersecurity in power electronics focuses on reducing vulnerabilities in the system, where most reside in the communication with the hardware devices. Although methods to secure communications lessen the probability and effects of cyber-attacks, discovering vulnerabilities is inevitable. This thesis attempts to provide a fail-safe approach to securing the system by targeting the safety of the power-electronic controller. This approach applies an additional security layer in case of a malicious or accidental controller firmware malfunction.

The online security …

Monte-Carlo-Based Analysis Of Traffic Flow For Urban Air Mobility Vehicles, Sara Ghayouraneh

Graduate Theses and Dissertations

The research conducted in this dissertation is focused on developing a simulation tool that can predict the traffic flow patterns of the Urban Air Mobility vehicles to alleviate some of the challenges related to their traffic management. First, an introduction to the concept of Urban Air Mobility is given, the usage of Automatic Dependent Surveillance-Broadcast systems for Urban Air Mobility vehicles is suggested and dynamic addressing concept is introduced as an answer to a part of air traffic management and address scarcity challenge for Urban air Mobility vehicles. Next, in order to simulate the traffic flow patterns of the Urban …

Experimental And Analysis Of Electromagnetic Characterization Of Biological And Non-Biological Materials In Microwave, Millimeter-Wave, And Terahertz Frequency Bands, Nagma Vohra

Graduate Theses and Dissertations

The goal of this research is to characterize the electromagnetic properties of biological and non-biological materials at terahertz (THz), millimeter-wave, and microwave frequency bands. The biological specimens are measured using the THz imaging and spectroscopy system, whereas the non-biological materials are measured using the microwave and millimeter-wave free-space system. These facilities are located in the Engineering Research Center at the University of Arkansas. The THz imaging system (TPS 3000) uses a Ti-Sapphire laser directed on the photoconductive antennas to generate a THz time domain pulse. Upon using the Fourier Transform, the spectrum of the pulsed THz signal includes frequencies from …

Distributed Modeling Approach For Electrical And Thermal Analysis Of High-Frequency Transistors, Amirreza Ghadimi Avval

Graduate Theses and Dissertations

The research conducted in this dissertation is focused on developing modeling approaches for analyzing high-frequency transistors and present solutions for optimizing the device output power and gain. First, a literature review of different transistor types utilized in high-frequency regions is conducted and gallium nitride high electron mobility transistor is identified as the promising device for these bands. Different structural configurations and operating modes of these transistors are explained, and their applications are discussed. Equivalent circuit models and physics-based models are also introduced and their limitations for analyzing the small-signal and large-signal behavior of these devices are explained. Next, a model …

Efficiently Estimating Survival Signature And Two-Terminal Reliability Of Heterogeneous Networks Through Multi-Objective Optimization, Daniel Bruno Lopes Da Silva

Graduate Theses and Dissertations

The two-terminal reliability problem is a classical reliability problem with applications in wired and wireless communication networks, electronic circuit design, computer networks, and electrical power distribution, among other systems. However, the two-terminal reliability problem is among the hardest combinatorial problems and is intractable for large, complex networks. Several exact methods to solve the two-terminal reliability problem have been proposed since the 1960s, but they have exponential time complexity in general. Hence, practical studies involving large network-type systems resort to approximation methods to estimate the system's reliability. One attractive approach for quantifying the reliability of complex systems is to use signatures, …