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2012

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Full-Text Articles in Power and Energy

Design And Installation Of Solar Home System (Shs) Promoted By The Department Of Energy, Steve Ivan P. Dalumpines Apr 2012

Design And Installation Of Solar Home System (Shs) Promoted By The Department Of Energy, Steve Ivan P. Dalumpines

Undergraduate Theses

EzSolar method is a simple method used in designing a small Solar Home System (SHS). It offers easy calculation and acceptable performance for the system. SHS is safe, clean, low maintenance, and long lasting as long as the system is properly designed and properly installed. The Department of Energy promotes the use of EZSolar method in designing and installing SHS in off-grid areas in the country as part of its electrification program. The study discusses the basics of design and installation of SHS. This manuscript also discussed a brief comparison between the EZSolar method and the conventional method of system …


Evaluation Of Ocean-Energy Conversion Based On Linear Generator Concepts, Michael Allen Stelzer Apr 2012

Evaluation Of Ocean-Energy Conversion Based On Linear Generator Concepts, Michael Allen Stelzer

Electrical & Computer Engineering Theses & Dissertations

A turbine generator is a device that converts mechanical rotation into electrical energy. Unfortunately, the primary driving force that has been used to provide this rotation has, thus far, been fossil fuels. Although fossil fuels have proven to be a reliable resource to continually supply the growing demand for electrical power, they are not without their financial and environmental drawbacks. With the continuously increasing demand for energy, it is hypothesized that the world may, in time, exhaust this precious natural resource and/or inflict permanent environmental damage upon our planet.

However, motions that occur in nature, such as ocean waves, can …


Application Of Game Theory To Improve The Defense Of The Smart Grid, Keith J. Ross Mar 2012

Application Of Game Theory To Improve The Defense Of The Smart Grid, Keith J. Ross

Theses and Dissertations

This thesis presents the development and evaluation of a distributed agent based system using reputation based trust and game theoretic techniques to improve the defense of the future smart grid from cyber-attack and equipment malfunctions. Future smart grid capabilities promise to leverage network technologies to revolutionize the production, transmission, distribution and consumption of electrical power. However, the internet like communication also increase the power grid's vulnerability to cyber-attack. This thesis uses simulation linking power systems with communication networks to demonstrate the benefits of a Distributed Decision Making Communication Enable Special Protection System (SPS) using reputation based trust and game theory …


A Ceramic-Anode Supported Low Temperature Solid Oxide Fuel Cell, Hanping Ding, Junjie Ge, Xingjian Xue Mar 2012

A Ceramic-Anode Supported Low Temperature Solid Oxide Fuel Cell, Hanping Ding, Junjie Ge, Xingjian Xue

Faculty Publications

We report the fabrication and evaluation of a ceramic-anode supported button cell LSCM-SDC/SDC/PBSC (thickness 400 μm/20 μm/20 μm). The anode/electrolyte assembly LSCM-SDC/SDC was co-fired at low temperature of 1250°C, where a slight amount of CuO was mixed with LSCM. The CuO (20.3 wt%) were impregnated into the porous substrate to enhance current collecting effect. The cell exhibited power density of 596 mWcm−2 and 381 mWcm−2 at 700°C with wet hydrogen and methane as the fuel respectively, where the silver paste was used as current collectors, the highest performance up to date for the cells with metal oxide anodes at this …


Design And Construction Of A Solar Operated Gate, Jacob Gardener Mar 2012

Design And Construction Of A Solar Operated Gate, Jacob Gardener

BioResource and Agricultural Engineering

This senior project discusses the design and construction of a solar operated gate. A solar panel is used to charge a battery, and then an inverter is used to run a garage door opener off the battery. The garage door opener operates a short lever arm which is connected to a longer lever arm which is connected to the gate. Each component and mounting mechanisms were designed and built to effectively provide the gate opening function. The finished product operates well, the gate opens in about 8 seconds after the button is pressed on the remote controller or wall mount …


Rapid Battery Interchange System, Mason Borda Mar 2012

Rapid Battery Interchange System, Mason Borda

Electrical Engineering

As our nation strives towards a departure from widespread use of fossil fuels, we must focus on a plan for what is to be the substitute for Internal Combustion Engine vehicles as well as the infrastructure to support this. The most popular alternative to the internal combustion engine is the electrically propelled vehicle, one that can provide us with many benefits including simplified construction, lower operational costs, and for the driving enthusiasts more torque. The prevailing issue in the widespread acceptance and use of the electric vehicle thus far is “range anxiety”. Range anxiety is defined as “The fear of …


Development Of Smart Pv Inverters For The Smart Grid, Yahia Baghzouz Feb 2012

Development Of Smart Pv Inverters For The Smart Grid, Yahia Baghzouz

NSTec UNLV Symposium

The Electric Grid has become more complex with recent technological developments. There are more alternative power sources and sensors added into the mix at every part of the grid. The Energy Meter has changed over the past several years as well. The older meters were checked only once a month with a meter reader, but the new "Smart" Meters are capable of reporting energy usage at fifteen minute intervals.


The Electrocatalytic Study Of Licoo2 In Air Electrode For Lithium-Air, Jun Gao, Wei Wu, Yan-Yan Tian, Yong Yang Feb 2012

The Electrocatalytic Study Of Licoo2 In Air Electrode For Lithium-Air, Jun Gao, Wei Wu, Yan-Yan Tian, Yong Yang

Journal of Electrochemistry

The LiCoO2 has been investigated as a new electrocatalyst for air electrodes using homemade lithium-air battery. The electrochemical performance and structural changes of the LiCoO2 based composite air electrodes have been studied. The results of CV, XRD and charge-discharge tests show that the composite air electrodes composed of LiCoO2 can greatly improve the discharge performance of lithium-air batteries. In particular when the composite air electrodes are charged to 4.1 V before further discharging, the obvious catalytic effects of LiCoO2 are attributed to higher valence state of the Co element in LiCoO2, esp. at charged …


Dissolved Oxygen Seawater Battery With Electrochemical Capacitance, Hai-Bo Xu, Yong-Hong Lu, Wei Zhang, Yan-Ting Yu, Chuan-Wei Yan, Ya-Ping Sun, Lian Zhong, Jian-Guo Liu, Yi Zheng, Bing Han, Yong-Liang Wang Feb 2012

Dissolved Oxygen Seawater Battery With Electrochemical Capacitance, Hai-Bo Xu, Yong-Hong Lu, Wei Zhang, Yan-Ting Yu, Chuan-Wei Yan, Ya-Ping Sun, Lian Zhong, Jian-Guo Liu, Yi Zheng, Bing Han, Yong-Liang Wang

Journal of Electrochemistry

A new concept of seawater battery with electrochemical capacitance (SWB-EC) has been proposed using carbon fibre brush (CFB) as the cathode material, and three testing prototypes have been made accordingly. The discharge performances of the CFB before- and after-oxidation and Mg alloy sacrifice anode were studied by cyclic voltammetry and constant current discharge tests under steady state conditions. Results show that the oxidized CFB exhibits the pseudo-capacitive characteristic and its activity of oxygen reduction reaction (ORR) in stirred seawater highly increases, comparing with the non-oxidized CFB. The open circuit potential of Mg alloy sacrifice anode is -1.74 V, having the …


Progress And Perspective Of Fuel Cell Technology, Ming Hou, Bao-Lian Yi Feb 2012

Progress And Perspective Of Fuel Cell Technology, Ming Hou, Bao-Lian Yi

Journal of Electrochemistry

Fuel cell, a clean and high-efficiency electrochemical power source, has being paid much attention worldwide recent years. In this paper, the progress and perspective of fuel cell technology are elucidated in detail. Fuel cells have been applied in some special fields such as spacecraft, shuttle and submarines. However, in the areas of transportation, stationary station and portable power source, fuel cells are still under demonstration due to the durability and cost problems. The reliability and surrounding survivability of fuel cells should be enhanced in the special application. Meanwhile, the durability and cost of fuel cells are the main issues to …


Preparation And Electrochemical Performance Of Lifepo4/C By Spray Drying Method Assisted With Organic Template, Quan-Bing Liu, Yang-Mei Jiang, Hui-Yu Song, Shi-Jun Liao Feb 2012

Preparation And Electrochemical Performance Of Lifepo4/C By Spray Drying Method Assisted With Organic Template, Quan-Bing Liu, Yang-Mei Jiang, Hui-Yu Song, Shi-Jun Liao

Journal of Electrochemistry

In this work, the LiFePO4/C composites were prepared by the spray drying and carbothermal method, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge measurements. The effects of the organic assisted templates on the morphologies and electrochemical properties of the LiFePO4/C composites were investigated. The results showed that the morphology and microstructure of the composites could be tuned by incorporating with the different templates. The morphology of the composite appeared to be solid microspheres if no organic template was added, while porous microspheres, nest-like …


Synthesis And Electrochemical Performance Of Xlifepo4·Yli3V2(Po4)3 Composites, Ping-Ping Ma, Zhi-Jian Liu, Jian-Hua Xia, Yu Chen, Pu Hu, Zhi-Chao Lu, Ding-Guo Xia Feb 2012

Synthesis And Electrochemical Performance Of Xlifepo4·Yli3V2(Po4)3 Composites, Ping-Ping Ma, Zhi-Jian Liu, Jian-Hua Xia, Yu Chen, Pu Hu, Zhi-Chao Lu, Ding-Guo Xia

Journal of Electrochemistry

A series of xLiFePO4·yLi3V2(PO4)3 composites were systematically synthesized through solid state reactions by variations in the proportions of LiFePO4 and Li3V2(PO4)3. The properties of the prepared compounds were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical measurements. The capacity of 162.7 mAh/g at 0.2 C rate was obtained with the relatively good cycle stability and good conductivity for 0.95LiFePO4·0.05Li3V2(PO4)3 due to more uniformed distributed and smaller particle sizes.


Preparation And Characterization Of Mno/Tin Anode For Lithium Ion Batteries, Gao-Jie Xu, Hai-Yan Yang, Peng-Xian Han, Li-Xue Zhang, Ke-Jun Zhang, Chuan-Jian Zhang, Yu-Hua Fan, Cai-Feng Bi, Guang-Lei Cui Feb 2012

Preparation And Characterization Of Mno/Tin Anode For Lithium Ion Batteries, Gao-Jie Xu, Hai-Yan Yang, Peng-Xian Han, Li-Xue Zhang, Ke-Jun Zhang, Chuan-Jian Zhang, Yu-Hua Fan, Cai-Feng Bi, Guang-Lei Cui

Journal of Electrochemistry

Manganese titanate (MnTiO3) powder was prepared via a sol-gel method using manganese acetate and tetrabutyl titanate as raw materials, and citric acid as a chelating agent. Through high temperature nitridation of MnTiO3 powder in ammonia, the MnO/TiN composite was obtained. The phase structure, composition and morphology of the composites were characterized by XRD, SEM and EDS. The electrochemical properties of the composite electrodes were studied by performing cyclic voltammetry, galvanostatic charge and discharge, and electrochemical impedance spectroscopy tests. The MnO/TiN electrode delivered specific capacities of 394 mAh·g-1 and 146 mAh·g-1 at the current density of …


Polar Field Oriented Control With 3rd Harmonic Injection, Martin Todd Hess Feb 2012

Polar Field Oriented Control With 3rd Harmonic Injection, Martin Todd Hess

Master's Theses

Abstract

POLAR FIELD-ORIENTED CONTROL

with

3RD HARMONIC INJECTION

Martin Todd Hess

Field Oriented Control (FOC), also known as vector control, is a widely used and well documented method for controlling Permanent-Magnet Synchronous Motors (PMSM) and induction motors. Almost invariably the orientation of the stator and rotor (field) fluxes are described in rectangular coordinates. In this thesis we explore the practicality of using polar coordinates.

Third harmonic injection is also a well-known technique that allows full utilization of the bus (DC-link), thus allowing the motor to run to full base speed without the use of field weakening. This technique potentially …


Managing The Future Energy Policy For Ireland: Examining The Role Of Nuclear Power, Declan Lynch, Angela Wright Feb 2012

Managing The Future Energy Policy For Ireland: Examining The Role Of Nuclear Power, Declan Lynch, Angela Wright

Dept. of Organisation & Professional Development Publications

This study assesses the attitudes and opinions of Irish people towards the use of nuclear power, and specifically examines the concept that Ireland should use nuclear power to generate electricity in the future. Currently, Ireland has a prohibition on nuclear power, with little debate or discussion on same, and with scant amounts of information published on the subject as it relates to Ireland. Conversely, from an international perspective, there is a significant volume of literature available covering all aspects of nuclear power, generated from over 50 years of nuclear power operations. Nuclear power technology is perceived as being a relatively …


A New Method For Node Ranking For Voltage Stability In Power Systems, Hongxiang Li Jan 2012

A New Method For Node Ranking For Voltage Stability In Power Systems, Hongxiang Li

Theses

The voltage collapse in power system is a major concern for reliable operation of these systems. In this thesis, a method is proposed to determine the load margins at load nodes (loadability limits). A good portion of the computation to obtain those margins is routinely done when solving the power flow problem, thus the computational effort is greatly reduced. The proposed method is based on the fact that when voltage collapse occurs the Jacobian matrix, that is calculated when performing power flow analysis, is singular. The relationships between the elements of the Jacobian matrix and the nodal powers are exploited …


Slides: Jisea Natural Gas Study: Potential U.S. Electric Power Futures, Jeffrey Logan Jan 2012

Slides: Jisea Natural Gas Study: Potential U.S. Electric Power Futures, Jeffrey Logan

Drawing the Blueprint for a Sustainable Natural Gas Future (January 18)

Presenter: Jeffrey Logan, Denver Museum of Nature and Science

4 slides


Can Morphology Tailoring Improve The Open Circuit Voltage Of Organic Solar Cells?, Biswajit Ray, M. S. Lundstrom, Muhammad A. Alam Jan 2012

Can Morphology Tailoring Improve The Open Circuit Voltage Of Organic Solar Cells?, Biswajit Ray, M. S. Lundstrom, Muhammad A. Alam

Birck and NCN Publications

While the effect of interfacial morphology on the short circuit current (ISC) of organic photovoltaic devices (OPVs) is well known, its impact on open circuit voltage (VOC) and fill-factor (FF) are less clear. Since the output power of a solar cell Pout = ISCVOCFF, such understanding is critical for designing high-performance, morphology-engineered OPVs. In this letter, we provide an explicit analytical proof that any effort to radically improve VOC by tailoring bulk heterojunction morphology is futile, because any increase in ISC due to larger interface area is counterbalanced by corresponding increase …


Solar Photovoltaic System Modeling And Control, Qing Xia Jan 2012

Solar Photovoltaic System Modeling And Control, Qing Xia

Electronic Theses and Dissertations

To realize the benefits of grid-connected photovoltaic system, it is extremely important to reduce energy losses and improve reliability of grid-connected PV systems with high PV penetration. In this thesis, three different Maximum Power Point Tracking (MPPT) strategies named as Perturbation & Observation MPPT, Incremental Conductance MPPT and Fuzzy Logic Control MPPT have been analyzed, simulated and compared with each other to improve the efficiency of power conversion. A general discussion to counteract partial shading effect in several aspects is also provided in this thesis. In order to improve reliability of the system, an optimum current control loop with suitable …


Smart Grid Communications, Christopher W. Asbery Jan 2012

Smart Grid Communications, Christopher W. Asbery

Theses and Dissertations--Electrical and Computer Engineering

Smart grid technologies are starting to be the future of electric power systems. These systems are giving the utilities detailed information about their systems in real time. One of the most challenging things of implementing smart grid applications is employing the communications into the systems. Understanding the available communications can help ease the transition to these smart grid applications. Many of the utility personnel are spending too much time trying to figure out which communication is better for their application or applications. So this thesis presents the different communication types available with discussing the different attributes in which these communication …


An Adaptive Utility Interactive Photovoltaic System Based On A Flexible Switch Matrix To Optimize Performance In Real-Time, Mahmoud Alahmad, Mohamed Amer Chaaban, Siu Kit Lau, Jonathan Shi, Jill Neal Jan 2012

An Adaptive Utility Interactive Photovoltaic System Based On A Flexible Switch Matrix To Optimize Performance In Real-Time, Mahmoud Alahmad, Mohamed Amer Chaaban, Siu Kit Lau, Jonathan Shi, Jill Neal

Durham School of Architectural Engineering and Construction: Faculty Publications

Reconfigurable architectures are of great interest to system designers to improve the system’s operation and efficiency. In this paper, we propose an adaptive utility interactive photovoltaic (PV) system based on a novel Flexible Switch array Matrix topology. This proposed system maximizes the generated power in real-time in response to operational conditions such as shading, soiling, mismatches, and module failure among others. The proposed system is a compromise in the utilization of power conditioning equipment to maximize energy capture and system efficiency. Simulation results demonstrate an average 13% improvement in efficiency when compared with the central inverter topology performance. A prototype …


Technical Feasibility Of Storage On Large Dish Stirling Systems, Charles E. Andraka, K Scott Rawlinson, Nathan P. Siegel Jan 2012

Technical Feasibility Of Storage On Large Dish Stirling Systems, Charles E. Andraka, K Scott Rawlinson, Nathan P. Siegel

Faculty Journal Articles

Dish-Stirling systems have been demonstrated to provide high-efficiency solar-only electrical generation, holding the world record at 31.25%. This high efficiency results in a system with a high possibility of meeting the DOE SunShot goal of $0.06/kWh. Current dish-Stirling systems do not incorporate thermal storage. For the next generation of non-intermittent and cost-competitive solar power plants, we propose a thermal energy storage system that combines latent (phase-change) energy transport and latent energy storage in order to match the isothermal input requirements of Stirling engines while also maximizing the exergetic efficiency of the entire system. This report takes an initial look at …


Characterization Of Deep Levels In N-Type And Semi-Insulating 4h-Sic Epitaxial Layers By Thermally Stimulated Current Spectroscopy, P. G. Muzykov, Ramesh Madhu Krishna, K. C. Mandal Jan 2012

Characterization Of Deep Levels In N-Type And Semi-Insulating 4h-Sic Epitaxial Layers By Thermally Stimulated Current Spectroscopy, P. G. Muzykov, Ramesh Madhu Krishna, K. C. Mandal

Faculty Publications

No abstract provided.


Coupled Electromagnetic And Heat Transfer Model For Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai, Sohan Birla, Jeyamkondan Subbiah, D. D. Jones, Harshanardhan Thippareddi Jan 2012

Coupled Electromagnetic And Heat Transfer Model For Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai, Sohan Birla, Jeyamkondan Subbiah, D. D. Jones, Harshanardhan Thippareddi

Department of Food Science and Technology: Faculty Publications

Microwave ovens are used extensively for heating a variety of not-ready-to-eat food products. Non-uniform heating of foods in microwave ovens is a major concern in assuring microbiological safety of such products. The non-uniform heating of foods is attributed by complex interaction of microwaves with foods. To understand this complex interaction, a comprehensive model was developed to solve coupled electromagnetic and heat transfer equations using finite-difference time-domain based commercial software. The simulation parameters, cell size, heating time step, and number of iterations for steady state electromagnetic field were optimized. The model was validated by 30 s heating profile of a cylindrical …


White Light Led Load System, Ronald Lu, Benjamin Ng Jan 2012

White Light Led Load System, Ronald Lu, Benjamin Ng

Electrical Engineering

No abstract provided.


On The Radius Of Convergence Of Interconnected Analytic Nonlinear Input-Output Systems, Makhin Thitsa, W. Steven Gray Jan 2012

On The Radius Of Convergence Of Interconnected Analytic Nonlinear Input-Output Systems, Makhin Thitsa, W. Steven Gray

Electrical & Computer Engineering Faculty Publications

A complete analysis is presented of the radii of convergence of the parallel, product, cascade and feedback interconnections of analytic nonlinear input-output systems represented as Fliess operators. Such operators are described by convergent functional series, which are indexed by words over a noncommutative alphabet. Their generating series are therefore specified in terms of noncommutative formal power series. Given growth conditions for the coefficients of the generating series for the subsystems, the radius of convergence of each interconnected system is computed assuming the subsystems are either all locally convergent or all globally convergent. In the process of deriving the radius of …


In Situ And Ex Situ Studies Of Molybdenum Thin Films Deposited By Rf And Dc Magnetron Sputtering As A Back Contact For Cigs Solar Cells, K. P. Aryal, H. Khatri, R. W. Collins, S. Marsillac Jan 2012

In Situ And Ex Situ Studies Of Molybdenum Thin Films Deposited By Rf And Dc Magnetron Sputtering As A Back Contact For Cigs Solar Cells, K. P. Aryal, H. Khatri, R. W. Collins, S. Marsillac

Electrical & Computer Engineering Faculty Publications

Molybdenum thin films were deposited by rf and dc magnetron sputtering and their properties analyzed with regards to their potential application as a back contact for CIGS solar cells. It is shown that both types of films tend to transition from tensile to compressive strain when the deposition pressure increases, while the conductivity and the grain size decreas. The nucleation of the films characterized by in situ and real time spectroscopic ellipsometry shows that both films follow a Volmer-Weber growth, with a higher surface roughness and lower deposition rate for the rf deposited films. The electronic relaxation time was then …


Fuzzy Interference System In Energy Demand Prediction, Thair Mahmoud, Daryoush Habibi, Octavian Bass, Stefan Lachowicz Jan 2012

Fuzzy Interference System In Energy Demand Prediction, Thair Mahmoud, Daryoush Habibi, Octavian Bass, Stefan Lachowicz

Research outputs 2012

No abstract available.


Measuring And Filtering Microwave Radiations Using Frequency Selective Surface Through Energy Saving Glass, Irfan Ullah Jan 2012

Measuring And Filtering Microwave Radiations Using Frequency Selective Surface Through Energy Saving Glass, Irfan Ullah

Theses: Doctorates and Masters

This thesis presents the results of our investigation into the measurement and filtering of microwave radiation, and the subsequent development of a microwave reduction solution for modern building architecture utilising Energy Saving Glass (ESG), in conjunction with Frequency Selective (FSS) surfaces through which useful signals can be filtered. In the investigation, radiation power density levels arising from the three common microwave sources (radio base stations, mobile phones, and microwave ovens) were measured, and the results were compared with the standards provided by the Australian Radiation Protection and Nuclear Safety Agency. For the radio base stations, the relationship between radiation intensity …


Modeling And Analysis Of Grid-Connected Solar-Wind Hybrid Power System, Sultan Altamimi Jan 2012

Modeling And Analysis Of Grid-Connected Solar-Wind Hybrid Power System, Sultan Altamimi

Dissertations and Theses @ UNI

Renewable energies are considered to be a significant part of the energy mix to assist the existing electricity demand and the future of electrical generation. Electrical power simulation software is increasingly being used to answer and determine the source of potential problems in the actual power system. To have a better understanding of an electrical power system, it is essential to validate all the components through simulation within an environment that allows accurate modeling of all power system components. This research presents modeling and analysis of an actual grid-connected solar-wind hybrid system at University of Northern Iowa campus in Cedar …