Comparison Of Organic And Inorganic Solar Photovoltaic Systems,
2018
California Polytechnic State University, San Luis Obispo
Comparison Of Organic And Inorganic Solar Photovoltaic Systems, Khulan Orgil
Electrical Engineering
This senior project report addresses the consumer’s need for accurate and easily accessible information when making a solar panel purchasing decision. Thus, the project analyzes and compares the costs and benefits of organic and inorganic photovoltaic systems during their life cycle. The cost comparison includes analysis of the environmental and economic costs of materials, production, installation, and disposal. The benefit comparison includes analysis of the economic, environmental, and social benefits accrued during the system’s lifetime. With the project’s data, consumers can make more informed decisions to fit their specific needs.
Dc-Dc 4-Switch Buck-Boost Converter For Energy Harvesting From Elliptical Machines,
2018
California Polytechnic State University – San Luis Obispo
Dc-Dc 4-Switch Buck-Boost Converter For Energy Harvesting From Elliptical Machines, Alexander C. Samietz, Gustavo Guzman
Electrical Engineering
The senior project report documents the process of replacing the network of resistors inside an elliptical machine with a DC-DC buck-boost converter. The buck-boost DC-DC converter accepts a wide input range of 5-60 Volts, with an output of 36 Volts for the most efficient use of the already available microinverter. The microinverter reclaims the lost energy and safely distributes it back to the electrical grid. The addition of this project reduces heat emissions from wasted energy and shrinks the carbon footprint of its users.
Investigation Of A Gan-Based Power Supply Topology Utilizing Solid State Transformer For Low Power Applications,
2018
University of Arkansas, Fayetteville
Investigation Of A Gan-Based Power Supply Topology Utilizing Solid State Transformer For Low Power Applications, Akrem Mohamed Elrajoubi
Graduate Theses and Dissertations
Gallium nitride (GaN) power devices exhibit a much lower gate capacitance for a similar on-resistance than its silicon counterparts, making it highly desirable for high-frequency operation in switching converters, which leads to their significant benefits on power density, cost, and system volume. High-density switching converters are being realized with GaN power devices due to their high switching speeds that reduce the size of energy-storage circuit components. The purpose of this dissertation research is to investigate a new isolated GaN AC/DC switching converter based on solid-state transformer configuration with a totem-pole power factor corrector (PFC) front-end, a half-bridge series-resonant converter (SRC) …
Automatic Performance Optimization On Heterogeneous Computer Systems Using Manycore Coprocessors,
2018
University of Arkansas, Fayetteville
Automatic Performance Optimization On Heterogeneous Computer Systems Using Manycore Coprocessors, Chenggang Lai
Graduate Theses and Dissertations
Emerging computer architectures and advanced computing technologies, such as Intel’s Many Integrated Core (MIC) Architecture and graphics processing units (GPU), provide a promising solution to employ parallelism for achieving high performance, scalability and low power consumption. As a result, accelerators have become a crucial part in developing supercomputers. Accelerators usually equip with different types of cores and memory. It will compel application developers to reach challenging performance goals. The added complexity has led to the development of task-based runtime systems, which allow complex computations to be expressed as task graphs, and rely on scheduling algorithms to perform load balancing between …
Intelligent Application Of Flexible Ac Transmission System Components In An Evolving Power Grid,
2018
University of Arkansas, Fayetteville
Intelligent Application Of Flexible Ac Transmission System Components In An Evolving Power Grid, Robert Wall
Graduate Theses and Dissertations
The world revolves around energy and the energy sector is continually transforming and evolving. The status quo has been set by governing agencies in the United States for completely reliable power. The demand for energy efficiency continually rises for multiple reasons. Technology has improved for all sectors of the power grid, including renewable energy sources, fault protection, and SMART grid technology. The addition of new energy sources has led to the decommissioning of inefficient energy sources. The implementation of new technologies and power load on a large scale, coupled with the removal of grid stabilizers has posed different challenges that …
Linking Lignin Source With Structural And Electrochemical Properties Of Lignin-Derived Carbon Materials,
2018
University of Kentucky
Linking Lignin Source With Structural And Electrochemical Properties Of Lignin-Derived Carbon Materials, Wenqi Li, Yan Zhang, Lalitendu Das, Yikai Wang, Mi Li, Namal Wanninayake, Yunqiao Pu, Doo Young Kim, Yang-Tse Cheng, Arthur J. Ragauskas, Jian Shi
Biosystems and Agricultural Engineering Faculty Publications
Valorization of lignin to high-value chemicals and products along with biofuel production is generally acknowledged as a technology platform that could significantly improve the economic viability of biorefinery operations. With a growing demand for electrical energy storage materials, lignin-derived activated carbon (AC) materials have received increasing attention in recent years. However, there is an apparent gap in our understanding of the impact of the lignin precursors (i.e., lignin structure, composition and inter-unit linkages) on the structural and electrochemical properties of the derived ACs. In the present study, lignin-derived ACs were prepared under identical conditions from two different lignin …
Continuous Monitoring Of Neutral Grounding Resistors And Reactors,
2018
The University of Western Ontario
Continuous Monitoring Of Neutral Grounding Resistors And Reactors, Rahim Jafari
Electronic Thesis and Dissertation Repository
Electrical power system components are designed three-phase balanced and symmetric with the internal connection of wye or delta. The common point of the wye-connected equipment, which is called neutral, is impedance grounded for many reasons such as fault ride through by controlling transient overvoltages, and limiting the ground overcurrents. Depending on the application, different neutral impedance grounding methods exist that employ resistors or reactors with/without neutral grounding transformers. These apparatuses are known as Neutral Grounding Devices (NGD). The most well-known sort of NGDsarethe Neutral Grounding Resistor (NGR) and Neutral Grounding Reactor (NGL) which are the main focus of this research …
Cfd Modeling On Hydrodynamic Characteristics Of Multiphase Counter-Current Flow In A Structured Packed Bed For Post-Combustion Co2 Capture,
2018
China University of Mining and Technology, China
Cfd Modeling On Hydrodynamic Characteristics Of Multiphase Counter-Current Flow In A Structured Packed Bed For Post-Combustion Co2 Capture, Li Yang, Fang Liu, Kozo Saito, Kunlei Liu
Mechanical Engineering Faculty Publications
Solvent-based post combustion CO2 capture is a promising technology for industrial application. Gas-liquid interfaces and interactions in the packed bed are considered one of the key factors affecting the overall CO2 absorption rate. Understanding the hydrodynamic characterizations within packed beds is essential to identify the appropriate enhanced mass transfer technique. However, multiphase counter-current flows in the structured packing typically used in these processes are complicated to visualize and optimize experimentally. In this paper, we aim to develop a comprehensive 3D multiphase, counter-current flow model to study the liquid/gas behavior on the surface of structured packing. The output from …
Secure Control And Operation Of Energy Cyber-Physical Systems Through Intelligent Agents,
2018
Florida International University
Secure Control And Operation Of Energy Cyber-Physical Systems Through Intelligent Agents, Mohamad El Hariri
FIU Electronic Theses and Dissertations
The operation of the smart grid is expected to be heavily reliant on microprocessor-based control. Thus, there is a strong need for interoperability standards to address the heterogeneous nature of the data in the smart grid. In this research, we analyzed in detail the security threats of the Generic Object Oriented Substation Events (GOOSE) and Sampled Measured Values (SMV) protocol mappings of the IEC 61850 data modeling standard, which is the most widely industry-accepted standard for power system automation and control. We found that there is a strong need for security solutions that are capable of defending the grid against …
Optimal Design Of A Switched Reluctance Motor With Magnetically Disconnected Rotor Modules Using A Design Of Experiments Differential Evolution Fea-Based Method,
2018
University of Kentucky
Optimal Design Of A Switched Reluctance Motor With Magnetically Disconnected Rotor Modules Using A Design Of Experiments Differential Evolution Fea-Based Method, Vandana Rallabandi, Jie Wu, Ping Zhou, David G. Dorrell, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Switched reluctance (SR) machines are attractive because they present relatively high efficiency and torque density in spite of lacking permanent magnets. This paper focuses on a two-objective optimization of an external rotor SR motor with a stator that has concentrated coils and a rotor with magnetically isolated modules. The objectives are minimum loss and mass, and 11 independent dimensionless geometric variables are considered as inputs that affect them. A combined design of experiments (DOE) and differential evolution (DE) approach is proposed. The DOE methodology is used to reduce the search space by eliminating from consideration input variable values, leading to …
Two-Level Surrogate-Assisted Differential Evolution Multi-Objective Optimization Of Electric Machines Using 3-D Fea,
2018
University of Kentucky
Two-Level Surrogate-Assisted Differential Evolution Multi-Objective Optimization Of Electric Machines Using 3-D Fea, Narges Taran, Dan M. Ionel, David G. Dorrell
Power and Energy Institute of Kentucky Faculty Publications
A two-level surrogate-assisted optimization algorithm is proposed for electric machine design using 3-D finite-element analysis (FEA). The algorithm achieves the optima with much fewer FEA evaluations than conventional methods. It is composed of interior and exterior levels. The exploration is performed mainly in the interior level, which evaluates hundreds of designs employing affordable kriging models. Then, the most promising designs are evaluated in the exterior loop with expensive 3-D FEA models. The sample pool is constructed in a self-adjustable and dynamic way. A hybrid stopping criterion is used to avoid unnecessary expensive function evaluations.
Game-Theoretic And Machine-Learning Techniques For Cyber-Physical Security And Resilience In Smart Grid,
2018
Florida International University
Game-Theoretic And Machine-Learning Techniques For Cyber-Physical Security And Resilience In Smart Grid, Longfei Wei
FIU Electronic Theses and Dissertations
The smart grid is the next-generation electrical infrastructure utilizing Information and Communication Technologies (ICTs), whose architecture is evolving from a utility-centric structure to a distributed Cyber-Physical System (CPS) integrated with a large-scale of renewable energy resources. However, meeting reliability objectives in the smart grid becomes increasingly challenging owing to the high penetration of renewable resources and changing weather conditions. Moreover, the cyber-physical attack targeted at the smart grid has become a major threat because millions of electronic devices interconnected via communication networks expose unprecedented vulnerabilities, thereby increasing the potential attack surface. This dissertation is aimed at developing novel game-theoretic and …
Recent Process In Transition-Metal-Oxide Based Catalysts For Oxygen Reduction Reaction,
2018
College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
Recent Process In Transition-Metal-Oxide Based Catalysts For Oxygen Reduction Reaction, Yao Wang, Zi-Dong Wei
Journal of Electrochemistry
Transition metal oxides (TMOs) based catalysts have become the most promising catalysts to be employed in anion exchange membrane fuel cell for the sluggish oxygen reduction reaction (ORR). However, their ORR activity is still far from that of the Pt-based catalysts. Therefore, it is important to develop high performance TMO based catalysts. Electrical conductivity and intrinsic activity have been regarded as the two keys to affect the ORR activity of the TMOs based catalysts. In this review, we focused on the recent progresses in the fundamental viewpoints on the electrical conductivity and intrinsic activity of the TMOs based ORR catalysts. …
Effects Of Sulfur-Containing Additive On Low Temperature Performance Of Graphite Anode,
2018
State Key Lab for Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Effects Of Sulfur-Containing Additive On Low Temperature Performance Of Graphite Anode, Ze-Li Wu, Ye-Zhen Zheng, Zhong-Ru Zhang, Yong Yang
Journal of Electrochemistry
The low temperature performance of lithium ion battery mainly depends on the graphite anode, and one of the research focuses is to improve the low temperature performance of the anode by additives. In this paper, the effects of different sulfur-containing functional groups such as DTD (ethylene sulfate), 1,3-PS (1,3-propane sultone) and ES (ethylene sulfite) on low temperature performances of artificial graphite materials were systematically studied. The results in density functional theory (DFT) calculations, cyclic voltammetry (CV), scanning electron microscopy (SEM) and charge-discharge measurement clearly demonstrated that all three sulfur-containing additives could participate in formation of films on the surface of …
Recent Advances In Non-Noble Metal Nanomaterials For Oxygen Evolution Electrocatalysis,
2018
Department of Chemistry College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, Jiangsu, China;
Recent Advances In Non-Noble Metal Nanomaterials For Oxygen Evolution Electrocatalysis, Dan-Dan Zhao, Nan Zhang, Ling-Zheng Bu, Qi Shao, Xiao-Qing Huang
Journal of Electrochemistry
Hydrogen is a kind of renewable energies with the merits of environmentally friendly, abundance and high weight energy density, which can replace the fossil energy. The electrolysis of water is regarded as the most effective way to generate hydrogen. Owing to the sluggish kinetics and large overpotential of the anode oxygen evolution reaction (OER), the efficiency of the cathode hydrogen evolution reaction is greatly limited. Therefore, it is highly desirable to explore efficient, stable and low cost electrocatalysts to reduce the overpotential of OER and improve the efficiency of hydrogen evolution. Based on the natural characteristics of non-noble metal catalysts …
Design Strategies Toward Highly Active Electrocatalysts For Oxygen Evolution Reaction,
2018
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research /Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China;
Design Strategies Toward Highly Active Electrocatalysts For Oxygen Evolution Reaction, Tang Tang, Wen-Jie Jiang, Shuai Niu, Jin-Song Hu
Journal of Electrochemistry
Electrocatalytic water splitting is pivotal for efficient and economical production of hydrogen and oxygen gasses. However, the efficiency of the whole device is largely limited by the oxygen evolution reaction (OER) at the anode due to its sluggish kinetics. Thus, it is imperative to develop inexpensive, highly active OER catalysts to lower the reaction barriers. By examining the underlying critical factors for OER performance, this review outlines general principles for designing efficient nanosized OER catalysts, including (1) enhancing the intrinsic activity of active site by electronic modulation, crystallinity modulation, phase control, defect engineering and spin state engineering; (2) designing appropriate …
Research Progresses In Improvement For Low Temperature Performance Of Lithium-Ion Batteries,
2018
Do-fluoride Chemicals Co., Ltd, Jiaozuo 454150, Henan, China;
Research Progresses In Improvement For Low Temperature Performance Of Lithium-Ion Batteries, Yue-Ru Gu, Wei-Min Zhao, Chang-Hu Su, Chuan-Jun Luo, Zhong-Ru Zhang, Xu-Jin Xue, Yong Yang
Journal of Electrochemistry
Lithium-ion batteries (LIBs) have become a new research hotspot due to their high energy density and long service life. However, the temperature characteristics, especially the poor performance at low temperatures, have seriously limited their wider applications. In this report, the research progresses in the low temperature performance of LIBs are reviewed. The main existing limitations of LIBs at low temperatures were systematically analyzed, and followed by discussion on the recent improvements in low temperature performances by developing novel cathode, electrolyte, and anode materials. The developments for improving the low temperature performance of LIBs are prospected. The three most important factors …
The New Application Of Battery-Electrode Reaction: Decoupled Hydrogen Production In Water Electrolysis,
2018
Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Fudan University, Shanghai 200433, China;
The New Application Of Battery-Electrode Reaction: Decoupled Hydrogen Production In Water Electrolysis, Yuan-Yuan Ma, Zhao-Wei Guo, Yong-Gang Wang, Yong-Yao Xia
Journal of Electrochemistry
Hydrogen has been considered as a promising alternative to unsustainable fossil fuels because of its high calorific value, clean and abundant resources. Water electrolysis combined with renewable energy is regarded as the best way for hydrogen production, which will become the foundation of future hydrogen economy. For the past few years, many efforts have been employed to develop the cheap and high-performance catalyst for hydrogen evolution reaction and oxygen evolution reaction. However,the coupled hydrogen and oxygen evolution and the use of the expensive membrane have greatly restricted the flexibility of the conventional water electrolysis, and hindered the utilization of renewable …
Recent Advances In Continuous Models Of Electrochemical Supercapacitors,
2018
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
Recent Advances In Continuous Models Of Electrochemical Supercapacitors, Hao-Tian Lu, Jing-Hong Zhou, Guang-Hua Ye, Xing-Gui Zhou
Journal of Electrochemistry
Electrochemical capacitors (supercapacitors) have been developed as a new type of energy storage device with high energy and power densities, which have the advantages of both fast charging-discharging as traditional capacitors and high energy density as batteries. Notable improvements in their electrochemical performance have been achieved in recent years owing to the recent advances in understanding of charge storage mechanisms and the development of advanced nanostructured materials. Recently, modeling and simulation of these supercapacitors has been applied as a useful approach to better understand the working mechanisms of the supercapacitors by describing the concentrations and electric fields inside the capacitors. …
Recent Progress In Organic Redox Flow Batteries,
2018
State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China;
Recent Progress In Organic Redox Flow Batteries, Li-Xing Xia, Hao Liu, Lin Liu, Zhan-Ao Tan
Journal of Electrochemistry
Redox flow batteries (RFBs) are promising candidate for balancing instability of grids caused by integration of intermittent renewable energies such as solar energy and wind energy. Along with wide deployments in solar energy and wind energy due to abundance and declining installation cost, it can be predicted that RFBs will enter a period of rapid development. Basically,RFBs are electrochemical energy storage devices that decouple energy and power of the system by storing liquid electrolyte in tanks outside battery system itself. Such a unique framework makes RFBs flexible and fulfills the various demands of grids. During battery operation, redox-active species are …
