Power and Energy Commons^™

A Nonlinear-Model-Based High-Bandwidth Current Sensor Design For Switching Current Measurement Of Wide Bandgap Devices, Xia Du, Liyang Du, Yuxiang Chen, Yuqui Wei, Andrea Stratta, H. Alan Mantooth

Electrical Engineering Faculty Publications and Presentations

With the growing adoption of wide bandgap devices in power electronic applications, current sensor design for switching current measurement has become more important. The demands for high accuracy, high bandwidth, low cost, compact size, and galvanic isolation pose significant design challenges. The conventional modeling approach for bandwidth analysis of current transformer sensors assumes that the magnetizing inductance remains constant, which does not always hold true in high-frequency operations. This can result in inaccurate bandwidth estimation and affect the overall performance of the current sensor. To address this limitation, this paper provides a comprehensive analysis of nonlinear modeling and bandwidth, considering …

Classification Of Electrical Current Used In Electroplastic Forming, Tyler Grimm

All Dissertations

Electrically assisted manufacturing (EAM) is the direct application of an electric current to a workpiece during manufacturing. This advanced manufacturing process has been shown to produce anomalous effects which extend beyond the current state of modeling of thermal influences. These purported non-thermal effects have collectively been termed electroplastic effects (EPEs).

While there is a distinct difference in results between steady-state (ideal DC) testing and pulsed current testing, the very definition of these two EAM methods has not been well established. A "long" pulse may be considered DC current; a "short" pulse may produce electroplastic effects; and even "steady-state" current shapes …

Design Approaches To Enhance Power Density In Power Converters For Traction Applications, Shamar Christian

Graduate Theses and Dissertations

This dissertation presents a design strategy to increase the power density for automotive Power Conversion Units (PCUs) consisting of DC-DC and DC-AC stages. The strategy significantly improves the volumetric power density, as evident by a proposed PCU constructed and tested having 55.6 kW/L, representing an 11.2 % improvement on the Department of Energy’s 2025 goal of 50 kW/L for the same power electronics architecture. The dissertation begins with a custom magnetic design procedure, based on optimization of a predetermined C-core geometrical relationship and custom Litz wire. It accounts for electrical and thermal tradeoffs to produce a magnetic structure to best …

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 …

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 …

Power Amplifier Based On Composite Injection-Voltaic Transistors, Nodira Batirdjanovna Alimova

Chemical Technology, Control and Management

The problem of high-current radio engineering devices is related to the fact that the use of high-power transistors and other semiconductor devices is limited by such a phenomenon as a secondary breakdown, in which there is a sharp decrease in the voltage on the device with simultaneous internal current lacing, and the device fails. To solve the problem of secondary breakdown, schemes have been proposed that operate stably at reverse voltage values 4-5 times higher than usual and at power dissipation 2-3 times higher than the maximum allowable power for an individual device. The problem is proposed to be solved …

Cobalt/Carbon Composites As Sulfur Hosts For High-Performance Lithium-Sulfur Batteries, Yun-Rui Yang, Huan-Huan Dong, Zhi-Qiang Hao, Xiang-Xi He, Zhuo Yang, Lin Li, Shu-Lei Chou

Journal of Electrochemistry

Lithium-sulfur (Li-S) battery is one of the promising energy storage devices because of its high energy density. However, the sulfur cathode suffers from sluggish electrochemical reaction kinetics, slow charge transfer, large volume expansion and severe shuttle effect of lithium polysulfides inevitably resulting in low reversible capacity, poor rate performance and short cycle life, limiting its practical applications. Herein, the recent progress of cobalt/carbon composites, including cobalt nanoparticles and cobalt single atoms, as the sulfur host materials in Li-S batteries is overviewed. In general, cobalt plays the role of electrocatalyst, which inhibits the shuttle effect of lithium polysulfides, accelerates the electrochemical …

Recent Advances Of Functional Electrolyte Additives For Lithium-Sulfur Batteries, Xiu-Qing Zhang, Shuai Tang, Yong-Zhu Fu

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries have become one of the most promising next-generation battery systems due to their high energy density and low cost. However, the application of Li-S batteries still faces critical challenges, such as the low conductivities of S and Li₂S, shuttle effect of polysulfides and dendrite growth of Li, etc. The optimization of the electrolyte can ameliorate the electrolyte|electrode interphase, conveniently regulating the parasitic reaction and improving the performance of the resultant batteries. The functional additives in electrolytes provide chances to tune the interphase and even the redox mechanism to improve the performance of the batteries. In …

Ultraviolet-Initiated In-Situ Cross-Linking Of Multifunctional Binder Backbones Enables Robust Lithium-Sulfur Batteries, Sha Li, Xiao Zhan, Gu-Lian Wang, Hui-Qun Wang, Wei-Ming Xiong, Li Zhang

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries show attractive prospects owing to their high theoretical energy density, but their commercialization still faces such challenges as lithium polysulfides shuttling, severe volume change and considerable polarization. These stubborn issues place higher demands on each component in the battery, such as the development of multifunctional binders with superior mechanical properties. Herein, ethoxylated trimethylolpropane triacrylate was firstly introduced into sulfur cathodes, and in-situ cross-linked by ultraviolet (UV) curing combined with traditional polyvinylidene difluoride binder (i.e., forming a binary binder, denoted as c-ETPTA/PVDF) to construct high-loading and durable Li-S batteries. The covalently cross-linked ETPTA framework not only significantly enhances …

Metals And Alloys As Catalytic Hosts Of Sulfur Cathode For Lithium-Sulfur Batteries, Zhen-Yu Wang, Xue-Ping Gao

Journal of Electrochemistry

Lithium-sulfur batteries are recognized as one of the most promising next-generation energy storage devices, owing to the high theoretical energy density of 2600 Wh·kg^–1. However, their application has been seriously hindered by the sluggish electrochemical reaction kinetics of elemental sulfur and discharged products (Li₂S₂/Li₂S), and the notorious “shuttle effect” of soluble intermediate lithium polysulfide species, leading to poor cycle stability, low sulfur utilization and inferior coulombic efficiency. Introducing catalytic hosts into sulfur cathode is an efficient path to propel the conversion of sulfur-contained species, thus preventing the dissolution and loss of active-sulfur …

Preface To The Special Issue On Lithium-Sulfur Batteries, Jia-Jia Chen, Ren-Jie Chen, Zhong Jin

Journal of Electrochemistry

No abstract provided.

Design And Development Of A Solar Module Health Monitoring Device, Elijah Madaris, Christopher Baden, Sandip Das

Symposium of Student Scholars

Solar power has emerged as a promising renewable clean energy source and installations of solar panels are increasing sharply year after year. Monitoring the power output and health of solar panels is critically important to ensure safe and reliable operation of a solar power plant throughout its operational lifetime. In this project, we have designed and built a low-cost electronic device that is capable of measuring the electrical parameters of a solar cell or module. The device consists of a microprocessor with integrated analog-to-digital converter, a supercapacitor bank, current sense amplifier, and electromechanical relays. The microprocessor performs data acquisition through …

Stabilizing Control Schemes For Grid-Connected Hybrid Pv-Energy Storage Systems, Indra Narayana Bhogaraju

LSU Doctoral Dissertations

A nonlinear stabilizing control scheme based on Lyapunov theory is proposed for a grid- connected hybrid photovoltaic (PV)/ battery/supercapacitor (SC) system. The system dynamics is developed in the stationary reference frame, and the state-space model of the system is derived and used to formulate the Lyapunov function (LF) candidate. The global asymptotic stability of the LF-based controller is discussed in detail. The real-time implementation feasibility of the proposed control scheme is validated through hardware-in-the-loop (HIL) studies of a grid- connected hybrid system under solar energy generation and grid load variations. To address the issue of digital computational time that leads …

Creating A Power System For A Robot, Nolan Hays

Scholars Week

I will be describing the process of creating the power system for the robot that will be competing in the 2023 IEEE Hardware Competition.

Recent Research Progresses Of Solid-State Lithium-Sulfur Batteries, Yu Luo, Ru-Qin Ma, Zheng-Liang Gong, Yong Yang

Journal of Electrochemistry

All solid-state lithium-sulfur batteries (ASSLSBs) are considered to be one of the most promising next-generation energy storage systems, due to the promises of high energy density and safety. Although the use of solid-state electrolytes could effectively suppress the "shuttle effect" and self-discharge of the conventional liquid lithium-sulfur (Li-S) battery, the commercialization of ASSLSBs has been seriously hampered by the electrolyte degradation, electrode/electrolyte interfacial deterioration, electrochemo-mechanical failure, lithium dendrite growth and electrode pulverization, etc. This paper provides a comprehensive review of recent research progresses on the solid-state electrolytes, sulfur-containing composite cathodes, lithium metal and lithium alloy anodes, and electrode/electrolyte interfaces in …

Bimetallic Compound Catalysts With Multiple Active Centers For Accelerated Polysulfide Conversion In Li-S Batteries, Wu-Xing Hua, Jing-Yi Xia, Zhong-Hao Hu, Huan Li, Wei Lv, Quan-Hong Yang

Journal of Electrochemistry

Practical applications of lithium-sulfur (Li-S) batteries are hindered mainly by the low sulfur utilization and severe capacity fading derived from the polysulfide shuttling. Catalysis is an effective remedy to those problems by promoting the conversion of polysulfides to reduce their accumulation in the electrolyte, which needs the catalyst to have efficient adsorption ability to soluble polysulfides and high activity for their conversion. In this work, we have proposed a bimetallic compound of NiCo₂S₄ anchored onto sulfur-doped graphene (NCS@SG) to fabricate a catalytic interlayer for Li-S batteries. Compared to CoS, the NiCo₂S₄ demonstrated much higher …

Preface To The Special Issue On Lithium-Sulfur Batteries, Jia-Jia Chen, Ren-Jie Chen, Zhong Jin

Journal of Electrochemistry

No abstract provided.

A Review On Solid-State Li-S Battery: From The Conversion Mechanism Of Sulfur To Engineering Design, Huan-Huan Jia, Chen-Ji Hu, Yi-Xiao Zhang, Li-Wei Chen

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries attract sustained attention because of their ultrahigh theoretical energy density of 2567 Wh·kg^–1 and the actual value over 600 Wh·kg^–1. Solid-state Li-S batteries (SSLSBs) emerge in the recent two decades because of the enhanced safety when compared to the liquid system. As for the SSLSBs, except for the difference in the conversion mechanism induced by the cathode materials themselves, the physical-chemical property of solid electrolytes (SEs) also significantly affects their electrochemical behaviors. On account of various reported Li-S batteries, the advantages and disadvantages in performance and the failure mechanism are discussed in this review. …

Coni-Based Bimetal-Organic Framework Derived Carbon Composites Multifunctionally Modified Separators For Lithium-Sulfur Batteries, Yan-Jie Wang, Hong-Yu Cheng, Ji-Yue Hou, Wen-Hao Yang, Rong-Wei Huang, Zhi-Cong Ni, Zi-Yi Zhu, Ying Wang, Ke-Yi Wei, Yi-Yong Zhang, Xue Li

Journal of Electrochemistry

The commercial application of lithium-sulfur batteries (LSB) is still limited by the irreversible capacity fading caused by the shuttle of lithium polysulfides (LIPS). To address this issue, a bimetal (nickel, cobalt)-organic framework (MOF) derived carbon, (Ni, Co)/C, was prepared to modify the separator. The multifunctionally modified separator effectively captures LIPS, ensuring the stability and reversibility of sulfur fixation, while providing catalytic activity and improving ionic conductivity. The cobalt metal has a larger coordination number, more pore structure distribution, larger specific surface area, more surface C=O, and smaller particle size to achieve a large and rapid chemical sulfur fixation. The high …

Statistical Analysis And Degradation Pathway Modeling Of Photovoltaic Minimodules With Varied Packaging Strategies, Sameera Nalin Venkat, Xuanji Yu, Jiqi Liu, Jakob Wegmueller, Jayvic Cristian Jimenez, Erika I. Barcelos, Hein Htet Aung, Roger H. French, Laura S. Bruckman

Faculty Scholarship

Degradation pathway models constructed using network structural equation modeling (netSEM) are used to study degradation modes and pathways active in photovoltaic (PV) system variants in exposure conditions of high humidity and temperature. This data-driven modeling technique enables the exploration of simultaneous pairwise and multiple regression relationships between variables in which several degradation modes are active in specific variants and exposure conditions. Durable and degrading variants are identified from the netSEM degradation mechanisms and pathways, along with potential ways to mitigate these pathways. A combination of domain knowledge and netSEM modeling shows that corrosion is the primary cause of the power …