Coreless And Conventional Axial Flux Permanent Magnet Motors For Solar Cars,
2018
University of Kentucky
Coreless And Conventional Axial Flux Permanent Magnet Motors For Solar Cars, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Axial flux permanent magnet (AFPM) motors are suitable options for solar-powered vehicles due to their compact structure and high torque density. Furthermore, certain types of AFPM machines may be configured without stator cores, which eliminates associated losses and cogging torque and simplifies the manufacturing and assembly. This paper examines two machine designs for use in the solar-powered vehicle of the challenger class-a single rotor, single stator conventional AFPM machine, and a coreless AFPM machine with multiple stator and rotor disks. The response surface methodology (RSM) is utilized for the systematic comparison of the conventional and coreless topologies and to select …
Decentralized Optimal Control With Application In Power System,
2018
Louisiana State University and Agricultural and Mechanical College
Decentralized Optimal Control With Application In Power System, Boyu Wang
LSU Doctoral Dissertations
An output-feedback decentralized optimal controller is proposed for power systems with renewable energy penetration. Renewable energy source is modeled similar to the classical generator model and is equipped with the unified power flow controller (UPFC). The transient performance of power system is considered and stability of the dynamical states are investigated. An offline decentralized optimal controller is designed that utilizes only the local states. The network comprises conventional synchronous generators as well as renewable sources with inverter equipped with UPFC. Subsequently, the optimal decentralized controller is compared to the initial stabilizing controller used to obtain the optimal controller. An online …
What Can I Do As A Student To Make A Positive Impact On The Environment?,
2018
University of Arkansas, Fayetteville
What Can I Do As A Student To Make A Positive Impact On The Environment?, Tammy Guthrie, Greg Herzig, Kathy Prophet, Cassie Kautzer
Middle School Lesson Plans
Students discover ways they can make a positive impact on the environment.
Power Electronics Powertrain Architectures For Hybrid And Solar Electric Airplanes With Distributed Propulsion,
2018
University of Kentucky
Power Electronics Powertrain Architectures For Hybrid And Solar Electric Airplanes With Distributed Propulsion, Damien Lawhorn, Vandana Rallabandi, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Distributed propulsion in aircraft has been shown to increase reliability and benefit aerodynamic performance. This paper discusses power electronic architectures and proposes control schemes suitable for distributed propulsion in hybrid and electric airplanes. Hybrid electric airplanes include permanent magnet synchronous generators driven by jet engines. The output of the generators is connected to the propulsion motors through back to back voltage source converters. Batteries, connected to the DC bus through buck-boost converters, are used to provide additional power to the propulsion motors during take off and climb. In the case of electric airplanes, the jet engine-permanent magnet generator system is …
Design Day Analysis - Forecasting Extreme Daily Natural Gas Demand,
2018
Marquette University
Design Day Analysis - Forecasting Extreme Daily Natural Gas Demand, David Joseph Kaftan
Master's Theses (2009 -)
This work provides a framework for Design Day analysis. First, we estimate the temperature conditions which are expected to be colder than all but one day in N years. This temperature is known as the Design Day condition. Then, we forecast an upper bound on natural gas demand when temperature is at the Design Day condition. Natural gas distribution companies (LDCs) need to meet demand during extreme cold days. Just as bridge builders design for a nominal load, natural gas distribution companies need to design for a nominal temperature. This nominal temperature is the Design Day condition. The Design Day …
Surrogate Affine Approximation Based Co-Optimization Of Transactive Flexibility, Uncertainty, And Energy,
2018
Cleveland State University
Surrogate Affine Approximation Based Co-Optimization Of Transactive Flexibility, Uncertainty, And Energy, Hongzing Ye
Electrical and Computer Engineering Faculty Publications
This study presents an approach to co-optimization of transactive flexibility, energy, and optimal injection-range of Variable Energy Resource (VER). Flexibility receives immense attention, as it is the essential resource to accommodate VERs in modern power systems. With a novel concept of transactive flexibility, the proposed approach proactively positions the flexible resources and optimizes the demand of flexibility. A surrogate affine approximation (SAA) method is proposed to solve the problem with variable infinite-constraint range in polynomial time. It is shown that SAA is more optimistic than the traditional affine policy in the power literature. The SAA method is also applicable to …
Investigation Of The Skin Effect In Alternating Currents,
2018
School of Science and Technology Singapore
Investigation Of The Skin Effect In Alternating Currents, Matthew Liang
The International Student Science Fair 2018
My research is on the investigation of the skin effect in alternating currents. The skin effect is when an alternating current tends to flow on the surface of the conductor, such that the current density is highest near the surface, and decreases with greater depths in the conductor. This is due to the alternating current inducing changing magnetic fields, which in turn induces currents that oppose the original flow of current, resisting the current flowing through the centre the most. This reduces the effective cross-sectional area of the conductor and increases the resistance, causing increased power losses. This effect becomes …
Low Voltage Ride Through Enhancement For Wind Turbines Equipped With Dfig Under Symmetrical Grid Faults,
2018
Department of Electrical Engineering, University of Dar es Salaam, Dar es Salaam
Low Voltage Ride Through Enhancement For Wind Turbines Equipped With Dfig Under Symmetrical Grid Faults, Francis Mwasilu
Tanzania Journal of Engineering and Technology (TJET)
In modern power systems with significant penetration of wind-turbines (WTs), improvement of low voltage ride through (LVRT) capability of WTs equipped with doubly-fed induction generators (DFIGs) is an important issue. Thus, this paper proposes a low voltage ride through (LVRT) strategy, which comprise of a capacitor connected in series with an inductor both connected in parallel to a resistor. The configuration is then connected to a small series resistor via a pair of antiparallel-Thyristors. The circuit and its switching control scheme of the proposed LVRT circuit are designed to: minimize the transition times, maintain the RSC connection to the rotor-windings, …
Recent Progress For Fe-N-C Electrocatalysts In Alkaline Fuel Cells,
2018
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China;
Recent Progress For Fe-N-C Electrocatalysts In Alkaline Fuel Cells, Xin Deng, Heng-Quan Chen, Ye Hu, Qing-Gang He
Journal of Electrochemistry
Fuel cells are highly recommended nowadays due to their intrinsic advantages such as high energy conversion efficiency, nearly no pollution, and convenient operation. With the development of anion exchange membrane, alkaline fuel cells have gone through a renaissance thanks to their superiorities such as faster reaction kinetics, wider choices for both fuels and electrocatalysts. It is essential to find an appropriate electrocatalyst for oxygen reduction reaction (ORR) to improve the performance of alkaline fuel cells. Further commercialization of the widely used Pt-based materials has suffered from disadvantages such as scarcity and high cost. As alternatives to largely investigated Pt-based materials, …
A Study Of Pulse Electrodeposition On Suppressing The Formation Of Lithium Dendrite,
2018
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
A Study Of Pulse Electrodeposition On Suppressing The Formation Of Lithium Dendrite, Wen-Jun Guo, Zi-Qiong Li, Ruo-Hao Ke, Dong-Fang Niu, Heng Xu, Xin-Sheng Zhang
Journal of Electrochemistry
A pulse charge method was used to suppress the formation of lithium dendrite on the copper electrode in 0.5 mol·L-1 LiBr/propylene carbonate (PC) electrolyte. The surface variation of lithium deposition was investigated by scanning electron microscope and impedance measurement. The SEM test showed that the lithium dendrites were formed on the copper electrode during the traditional process of electrodeposition. However, the formed dendrite was suppressed by pulse charge method. The results of the impedance measurement confirmed that the pulse electrodeposition could suppress the dendrite under the optimized duty ratio (0.5). The long single pulse deposition time decreased the resistance …
Pt/G-C3N4 Nanosheet For Visible Light-Induced Enhancement Of The Activity For Formic Acid Electro-Oxidation,
2018
Institute of Advanced Chemical Power Sources, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China;School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China;
Pt/G-C3N4 Nanosheet For Visible Light-Induced Enhancement Of The Activity For Formic Acid Electro-Oxidation, Yong-Rong Sun, Chun-Yu Du, Guo-Kang Han, Ya-Jing Wang, Yun-Zhi Gao, Ge-Ping Yin
Journal of Electrochemistry
By using graphitic carbon nitride nanosheet (g-C3N4 nanosheet) as a support,Pt/g-C3N4 nanosheet catalyst was fabricated by microwave assisted polylol process. The nanoparticles size,composition,structure and optical properties of Pt/g-C3N4 nanosheet were characterized by TEM,XRD,XPS and UV-Vis diffuse reflectance spectroscopy. Comparing with the catalytic activities toward formic acid electro-oxidation under dark and visible light illumination,the superior activity of Pt/g-C3N4 nanosheet catalyst was achieved under visible light illumination. This visible light-driven enhancement in the formic acid performance could be attributed to the plasmon-induced electron-hole separation on g-C3N4 with …
Carbon Composite Fe3O4 Nanoparticles Based Electrochemical Sensor For Hydrogen Peroxide Detection,
2018
Institute of Environmental and Analytical Sciences, College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, Henan, China;
Carbon Composite Fe3O4 Nanoparticles Based Electrochemical Sensor For Hydrogen Peroxide Detection, Si-Yu Zhang, Hui-Juan Wang, Shu-Fang Li, Jian-Ying Qu
Journal of Electrochemistry
In this work, a novel hydrogen peroxide electrochemical sensor was constructed with ferroferric oxide (Fe3O4) magnetic nanoparticles, which demonstrated good electrocatalytic activity for hydrogen peroxide. There existed a good linear relationship between the concentration of hydrogen peroxide and the oxidation peak current in the range of 1.00 × 10-6 ~ 1.00 × 10-3 mol·L-1 (R = 0.9980) with the detection limit of 6.60 × 10-7 mol·L-1. The sensor exhibited good anti-interference ability, high reproducibility and stability.
Lead Modified Nanoporous Platinum Electro-Catalysts For Formic Acid Oxidation,
2018
School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China;
Lead Modified Nanoporous Platinum Electro-Catalysts For Formic Acid Oxidation, Yuan-Yuan Zhang, Qing-Feng Yi, Ge-Kun-Kun Zuo, Tao Zou, Xiao-Ping Liu, Xiu-Lin Zhou
Journal of Electrochemistry
Platinum (Pt) catalysts modified by other suitable metals significantly enhance their electrochemical activities for formic acid oxidation. In this work, a titanium-supported nanoporous network platinum (nanoPt/Ti) electrode was prepared using a hydrothermal method. The as-prepared nanoPt/Ti electrode was modified with a certain amount of lead by using cyclic voltammetry for different scan cycle numbers (n), namely, n = 10, 15, 20 and 30, to synthesize the novel lead-modified nanoporous Pt (nanoPb(n)-Pt/Ti) electrodes. Electro-oxidation of formic acid on these electrodes was studied with cyclic voltammetry (CV), chronoamperometry and chronopotentiometry in sulfuric acid solution. CV curves showed that both nanoPt/Ti …
Chemical Stability Investigations Of Catalyst Layer In Pemfc,
2018
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China; University of Chinese Academy of Sciences, Beijing 100039, China;
Chemical Stability Investigations Of Catalyst Layer In Pemfc, Yan-Yan Gao, Ming Hou, Yong-Yi Jiang, Dong Liang, Jun Ai, Li-Min Zheng
Journal of Electrochemistry
This work was intended to study the effect of free radicals on the chemical stability of catalyst layer via ex situ accelerated stress test (AST). Fenton reagent was used as the free radical provider in this research. Apart from the decomposition of Nafion in catalyst layer, the agglomerated Pt nanoparticles and the corroded carbon support were also observed after being treated in Fenton reagent for 100 h. Firstly, the existence of fluoride (F) ions evidenced the chemical decomposation of Nafion after being attacked by trace radical species, which was supported by the intensity decrease in the C-F stretching and vibration …
Co3(Hcoo)6@Rgo As A Promising Anode For Lithium Ion Batteries,
2018
State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, iChem (Collaborative Innovation Center of Chemistry for Energy Materials), Xiamen University, Xiamen 361005, China;
Co3(Hcoo)6@Rgo As A Promising Anode For Lithium Ion Batteries, Heng Jiang, Jing-Min Fan, Ming-Sen Zheng, Quan-Feng Dong
Journal of Electrochemistry
Metal–organic framework(MOF) is a kind of novel electrode materials for lithium ion batteries. Here, a composite material Co3(HCOO)6@rGO was synthesized for the first time by in situ loading of Co3(HCOO)6 on rGO (reduced oxide graphene) through a solution chemistry method. As an anode material for lithium ion batteries, it exhibited an excellent cycle stability as well as a large reversible capacity of 926 mAh·g-1 at a current density of 500 mA·g-1 after 100 cycles within the voltage range of 0.02 ~ 3.0 V vs. Li/Li+ with a good rate capability. …
Preparations And Electrochemical Performances Of Carbon Coated Silicon/Graphite Composites,
2018
College of Energy, Xiamen University, Xiamen 361005, Fujian, China;
Preparations And Electrochemical Performances Of Carbon Coated Silicon/Graphite Composites, Tian-Yi Gao, Zheng-Liang Gong
Journal of Electrochemistry
In this work, the carbon coated silicon (Si@C) composite materials were synthesized based on the industrial silicon powder (600 meshes) via a high energy ball milling combing with in-situ carbon coating (carbonization) method. The Si@C/graphite (Si/C) composite anode materials were prepared by a simple mechanical ball-milling approach. The effects of carbon coating and the ratio of Si to graphite on electrochemical performances of Si/graphite composite materials were investigated systematically. Compared with the nano-Si/graphite composites, the Si/C composites showed higher reversible capacity, better rate capability and cycle performance. The Si@C materials composited of amorphous carbon and crystal silicon with the primary …
Investigation Of The Skin Effect In Alternating Currents,
2018
School of Science and Technology Singapore
Investigation Of The Skin Effect In Alternating Currents, Matthew Liang
The International Student Science Fair 2018
My research is on the investigation of the skin effect in alternating currents. My project is broken down into 4 sub-aims. The first aim would be, to be able to mathematically model the distribution of current in the radius of the wire, which consists of the applications of the Maxwell equation and solving zeroth order differential Bessel equations of the first kind. The next aim would be to computationally plot out the desired current readings as the depth of the wire increases from the surface, using the Matlab software. The third aim that I have would be conducting an experiment, …
Energy Conversion System For Travelers (Ecost),
2018
Chulalongkorn University Demonstration Secondary School
Energy Conversion System For Travelers (Ecost), Thipok Bovornratanaraks
The International Student Science Fair 2018
We have innovated “The Energy Conversion System for Travelers” or the ECoST. With the fact that most travelers have wheeled cabin-bags, whilst walking, the wheels will rotate so why don’t we harvest electricity from this kinetic energy? We thus install our innovation, the ECoST, to the bag to generate electricity from the spinning wheels. The electricity is then kept in the storage unit and ready to charge your empty battery devices in an emergency case via a USB port. To make life easy, our ECoST was designed to replicate the power bank charging method; therefore, we can charge …
Wind Turbine Design: Analysis And Experimentation Of Electro-Magnetic Alternator Design,
2018
SPU
Wind Turbine Design: Analysis And Experimentation Of Electro-Magnetic Alternator Design, Mark Hans Ewald Steinke
Honors Projects
This article explores the alternator designs for small scale wind turbines and the aspects that affect the performance of these alternators. It explores the design and testing process used to quantify, visualize, and understand the relationship between the wind turbine stator design and the performance. Additionally, the paper analyzes the data collection method using a test jig powered by a hydraulic motor set up by previous groups of students and the data intended to be collected using actual field tests on Whidbey Island located at Camp Casey. These tests were intended to identify favorable combinations of alternators and blades. However, …
Analog Sorting Using Pulse Width Modulation,
2018
California Polytechnic State University, San Luis Obispo
Analog Sorting Using Pulse Width Modulation, Riley C. Olson
Computer Engineering
As time goes on, computers become more and more powerful. However, as processing time becomes less of a limiting factor for computing tasks, power consumption takes its place for many tasks. This paper proposes and tests a new method for sorting analog signals. This new sorting method converts analog signals into Pulse Width Modulated(PWM) signals of varying duty cycle , which are then sorted by a simple network of combinational logic, and then converted to a normal binary representation. In order to implement this new method, multiple circuits had to be designed and and tested to ensure their functionality and …
