Power and Energy Commons^™

The Design, Implementation, Assessment, And Evaluation Of A Power Systems Protection Laboratory Curriculum, Jennifer Ferris

Dissertations and Theses

Over the last the last three decades, there has been a significant and documented decrease of power engineering curriculum within U.S. electrical engineering programs. Development of lifelong learners capable of critical and independent thinking is required to replace the large number of upcoming retirees from the industry and to prepare for the engineering challenges new technologies, laws and regulations are bringing to the electrical power system. In response to these challenges, Portland State University redesigned its BSEE and MSECE power engineering programs in order to create a launching pad for successful power engineering careers. A course series on power system …

Influence Of Reduction Promoters On Stability Of Cobalt/Γ-Alumina Fischer-Tropsch Synthesis Catalysts, Gary Jacobs, Wenping Ma, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

This focused review article underscores how metal reduction promoters can impact deactivation phenomena associated with cobalt Fischer-Tropsch synthesis catalysts. Promoters can exacerbate sintering if the additional cobalt metal clusters, formed as a result of the promoting effect, are in close proximity at the nanoscale to other cobalt particles on the surface. Recent efforts have shown that when promoters are used to facilitate the reduction of small crystallites with the aim of increasing surface Co⁰ site densities (e.g., in research catalysts), ultra-small crystallites (e.g., < 2–4.4 nm) formed are more susceptible to oxidation at high conversion relative to larger ones. The choice of promoter is important, as certain metals (e.g., Au) that promote cobalt oxide reduction can separate from cobalt during oxidation-reduction (regeneration) cycles. Finally, some elements have been identified to promote reduction but either poison the surface of Co⁰ (e.g., Cu), or produce excessive light gas selectivity (e.g., Cu and Pd, or Au at …

Boosty-Bit: Power For Pint-Sized Projects, Timothy Grijalva

Electrical Engineering

In order to make it easier for hobbyists to create small portable microcontroller based electronics projects, I have created Boosty-bit, a tiny DC-DC boost convert that runs off a single alkaline battery cell (AA or AAA). The Boosty-bit converter can source up to 250mA @ 3.3v, making it ideal for many microcontroller based projects. In addition to power management, Boosty-bit is also physically small, allowing it to fit inside pen/marker-sized enclosures along with a AAA battery and a microcontroller. Boosty-bit aims to be the ideal solution for “makers” who desire portability and compact form factors in their projects.

Electrochemical Performance Of Si-C Composites Prepared By Discharge-Plasma Assisted Milling, Yu-Long Chen, Ren-Zong Hu, Hui Liu, Wei Sun, Min Zhu

Journal of Electrochemistry

Silicon-carbon (Si-C) composites, with microstructure of multi-scaled Si particles being homogenously dispersed in micro-sized carbon matrix, had been prepared by dielectric barrier discharge plasma assisted two-step milling for the first time. The Si-C composite anode had a discharge capacity of 1259 mAh·g^-1 at the first cycle, while the capacity retained 474 and 396 mAh·g^-1 after 20 and 100 cycles, respectively. Charge-discharge curves and AC impedance response indicated that both silicon and carbon phases in the composite anode were involved during the lithiation/delithiation reactions and the electron transport resistance in the Si-C composite anode was much lower than that …

Study On Carbon Supported Pd Catalysts Modified By Phosphomolybdic Acid For H2O2 Electrocatalytic Reduction, Li-Mei Sun, Cheng Zhang, Ying-Rong Bao, Hong-Xia Li

Journal of Electrochemistry

The Pd/C catalyst was prepared with the chemical reduction method, and phosphomolybdic acid (PMA) was modified on the Pd/C catalyst using the dipping method. The compositions and structures of the Pd/C and Pd/C modified by phosphomolybdic acid (PMA-Pd/C) catalysts were characterized with X-ray diffraction and Fourier Transform infrared spectroscopy analyses. The electrocatalytic activity and stability of the catalysts for the reduction of hydrogen peroxide (H₂O₂) were studied using cyclic voltammetry and chronoamperometry. The results showed that the phosphomolybdic acid was tightly fixed on the surface of Pd/C catalyst through the chemical interaction. The eletrocatalytic activity of …

Electrochemical Oxidation Of Ammonium Nitrite In Absorption Solution Of Flue Gas, Yong-Hong Lu, Xiao-Bo Dong, Li-Sha Wang, Yan Liu, Chen-Jian Zhu, Hai-Bo Xu

Journal of Electrochemistry

In order to make full uses of ammonium nitrite in absorption solution from flue gas simultaneous desulfurization, denitrification and demercurization processes, here the electrochemical oxidation method was used to transform ammonium nitrite into ammonium nitrate. By using polarization curve, cyclic voltammogram and galvanostatic methods, suitable electrode materials were evaluated and chosen. The influence of electrolyte composition was discussed and the appropriate process parameters were obtained. Finally, the effect of electrochemical oxidation was confirmed by chemical analysis method. In 0.05 mol·L^-1 NaNO₂ + 0.05 mol·L^-1 (NH₄)₂SO₄ simulated absorption solution (5 L, pH = …

Preparation Of High Performance Porous Silicon Powders By Etching Al-Si Alloy In Acid Solution For Lithium Ion Battery, Shi-Ji Hao, Chun-Li Li, Kai Zhu, Ping Zhang, Zhi-Yu Jiang

Journal of Electrochemistry

Porous silicon powders prepared by etching Al-Si alloy using an acid solution was reported in the first time. The morphology and structure of as-obtained material were investigated using scanning electron microscopy (SEM) and X-ray diffraction (XRD) method. It was found that the spongy porous silicon powders presented well crystalline structure and consisted of nano-Si particles. The particle size of porous Si powders was about 20 μm, and the specific surface area was 102.7 m²·g^-1. The electrochemical properties of porous silicon powders were evaluated as an anode material for lithium ion batteries. The material proportion in the …

Pulse Electrodeposition Of Pd-Ni Alloy Nanoparticles For Electrocatalytic Oxidation Of Formic Acid, Fang-Zu Yang, Jun-Pei Yue, Zhong-Qun Tian, Shao-Min Zhou

Journal of Electrochemistry

The Pd-Ni alloy nanoparticles with nickel atomic contents of 12.0%, 16.4% and 22.6% were successfully electrodeposited from a Pd-Ni alloy electrolyte by square wave pulse plating. The alloy nanoparticles were in the spherical shape with a diameter of 50 ~ 80 nm. As the growth potential of the alloy was negatively shifted, the nickel content of the alloy was increased, and the size of the nanoparticles was almost the same, whereas the number, the degree of crosslinking and the real active area of the nanoparticles were increased. As the nickel content of the alloy nanoparticles increased, the peak current for …

Synthesis And Electrochemical Properties Of Lico1-XMgXMno4 And Lico1-XAlXMno4 (X= 0, 0.02, 0.05, 0.1) As Positive Materials For Lithium-Ion Batteries, Mei-Ling You, Qing-Song Tong, Xiu-Hua Li, Min Lin, Xing-Kang Huang, Yong Yang

Journal of Electrochemistry

The Al-doped and Mg-doped LiCoMnO₄ materials were synthesized through solid-state reaction. The effects of doping amounts of Mg and Al on the initial capacities, discharge plateaus, and cycle performances were investigated. The morphologies and structures of the as-prepared materials were studied by scanning electron microscopy and powder X-ray diffraction. The results indicate that the as-prepared samples were composed of uniform, well-crystallized particles. The pristine LiCoMnO₄ possessed an initial capacity of 87.0 mAh·g^-1, while LiCo_0.98Mg_0.02MnO₄ and LiCo_0.98Al_0.02MnO₄ delivered 91.3 and 93.6 mAh·g^-1, respectively. The proper …

Fabrication And Impedance Performance Of Gradient Lani0.6Fe0.4O3-δ-Gd0.2Ce0.8O2 Composite Cathodes For Intermediate Temperature Solid Oxide Fuel Cell, Yang Li, Bo Huang, Meng Yuan, Zhi-Qiu Zhang, Zong-Yao Liu, Xu-Chen Tang, Xin-Jian Zhu

Journal of Electrochemistry

A LNF-GDC composite cathode with a gradual change in the composition between ScSZ electrolyte and LNF cathode was fabricated to reduce the cathode polarization resistance (R_p). The gradual change in composition between ScSZ electrolyte and LNF cathode shows the decreases in the charge transfer resistance (R_ct) and gas phase diffusion resistance (R_d). The results revealed that the Rp value, measuring 0.452 Ω·cm² at 750 °C, was the lowest for LNF-GDC composite cathodes with three layers and gradient changes in composition between ScSZ and LNF (Cathode C),, whereas the Rp value of 70%LNF-30%GDC composite …

Preparation Of Pd/Tio2/C Catalyst And Its Electrocatalytic Performance In Basic Solution For Ethanol Oxidation, Qiao-Xia Li, Yi-Chao Yang, Ming-Shuang Liu, Hong-Min Mao, Qun-Jie Xu

Journal of Electrochemistry

Nanoparticles TiO₂ were prepared by hydrothermal method using precursor tetrabutyl titanate. The Pd/TiO₂/C catalyst was synthesized by liquid phase reducing method supported on nano TiO₂ and Vulcan carbon XC-72. The Pd/TiO₂/C catalyst was characterized by XRD, TEM, cyclic voltammetry, and chronopotentiometry. XRD confirmed the face-centered cubic structure of Pd particles, and TEM indicated that Pd particles (size 3 ~ 4 nm) dispersed uniformly on TiO₂ and carbon XC-72. The results from cyclic voltammogram and chronopotentiogram showed the higher ethanol oxidation activity and stability of Pd/TiO₂/C catalyst (20% Pd) as compared with …

Design And Development Of A Novel Glucose Biosensor Based On The Ferrocene-Functionalized Fe3O4 Nanoparticles/Carbon Nanotubes/Chitosan Nanocomposite Film Modified Electrode, Hua-Ping Peng, Dai-Jun Zha, Wei Chen, Ai-Lin Liu, Xin-Hua Lin

Journal of Electrochemistry

A novel platform for the fabrication of glucose biosensor was successfully constructed by entrapping glucose oxidase (GOD) in a ferrocene monocarboxylic acid-aminated Fe₃O₄ magnetic nanoparticles conjugate (FMC-AFNPs)/chitosan (CS)/multiwall carbon nanotubes (MWNTs) nanocomposite. The formation of FMC-AFNPs could effectively prevent the leakage of ferrocene and retain its electrochemical activity. This GOD/FMC-AFNPs/CS/MWNTs matrix provided a biocompatible microenvironment for retaining the native activity of the immobilized GOD. Moreover, the presence of MWNTs enhanced the charge-transport properties of the composite and facilitated electron transfer between the GOD and the electrode for the electrocatalysis of glucose. Under the optimal conditions the designed …

Household Solar Power System, He Jiang

Dissertations, Master's Theses and Master's Reports - Open

Photovoltaic power has become one of the most popular research area in new energy field. In this report, the case of household solar power system is presented. Based on the Matlab environment, the simulation is built by using Simulink and SimPowerSystem. There are four parts in a household solar system, solar cell, MPPT system, battery and power consumer. Solar cell and MPPT system are been studied and analyzed individually. The system with MPPT generates 30% more energy than the system without MPPT. After simulating the household system, it is can be seen that the power which generated by the system …

Hvac System Analysis And Energy Audit: The Providence Athenaeum, Nicholas Farland, Trevor Larson, Justin Taylor, Cameron Wendler, Anthony Ruocco, Janet Baldwin, Arnold Robinson

Engineering and Construction Management

To evaluate the impact of potential modifications to the HVAC system the Historical Value Adding Consultants developed a building energy model. The building energy model was constructed using a Microsoft Excel spreadsheet that utilizes typical meteorological year (TMY) data to determine the average energy usage of the Athenaeum for a typical year. The model has been validated against actual energy usage and is used to identify and quantify energy savings resulting from design alternatives.

Short-Term Load Forecasting Using Neural Network For Future Smart Grid Application, Jixuan Zheng

Electronic Theses and Dissertations

Short-term load forecasting of power system has been a classic problem for a long time. Not merely it has been researched extensively and intensively, but also a variety of forecasting methods has been raised.

This thesis outlines some aspects and functions of smart meter. It also presents different policies and current statuses as well as future projects and objectives of SG development in several countries.

Then the thesis compares main aspects about latest products of smart meter from different companies.

Lastly, three types of prediction models are established in MATLAB to emulate the functions of smart grid in the short-term …

Dc Microgrid Stabilization Through Fuzzy Control Of Interleaved, Heterogeneous Storage Elements, Robert David Smith

Dissertations, Master's Theses and Master's Reports - Open

As microgrid power systems gain prevalence and renewable energy comprises greater and greater portions of distributed generation, energy storage becomes important to offset the higher variance of renewable energy sources and maximize their usefulness. One of the emerging techniques is to utilize a combination of lead-acid batteries and ultracapacitors to provide both short and long-term stabilization to microgrid systems.

The different energy and power characteristics of batteries and ultracapacitors imply that they ought to be utilized in different ways. Traditional linear controls can use these energy storage systems to stabilize a power grid, but cannot effect more complex interactions. This …

Building Temperature Control With Intelligent Methods, Feng Zhang

Electronic Theses and Dissertations

Temperature control is important for both human comfort and the need in industry. In the thesis, two good intelligent control methods are compared to find their advantages and disadvantages. Matlab is used as the tool to make models and process calculations. The building model is one simple room in Akwesasne in New York State and the target is to keep the temperature indoor around 22 degree Centigrade from 12/29/2013 to 12/31/2013. Heat pump is used to provide or absorb heat. All data in the experiments is from JRibal Environmental eXchange network and PJM. The first method is fuzzy neural network …

Simplified Method To Derive The Kalman Filter Covariance Matrices To Predict Wind Speeds From A Nwp Model, Conor Lynch, Michael J. O'Mahony, Ted Scully

NIMBUS Articles

This paper espouses a simplified approach to predict wind speed 1 hour ahead for a wind turbine located on the Cork Institute of Technology (CIT) college campus by utilising a Kalman Filter to predict the bias between a campus based turbine and the output from a Numerical Weather Prediction (NWP) model for Cork Airport.

Furthermore, this paper investigates the optimum number of samples required (n) in a fixed sampling interval process to derive the covariance matrix of the system equation Qt and the covariance matrix of the observation equation Rt . The main contents of this paper include …

Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera

Dissertations

This research presents a novel fully integrated energy harvester, matching network, multi-stage RF-DC rectifier, mode selector, RC oscillator, LC oscillator, and X-band power amplifier implemented in IBM 0.18-µm RF CMOS technology. We investigated different matching schemes, antennas, and rectifiers with focus on the interaction between building blocks. Currently the power amplifier gives the maximum output power of 5.23 dBm at 9.1GHz. The entire RFID tag circuit was designed to operate in low power consumption. Voltage sensor circuit which generates the enable signal was designed to operate in very low current. All the test blocks of the RFID tag were tested. …

Intelligent Approaches For Modeling And Optimizing Hvac Systems, Iii Raymond Tesiero

Dissertations

Advanced energy management control systems (EMCS), or building automation systems (BAS), offer an excellent means of reducing energy consumption in heating, ventilating, and air conditioning (HVAC) systems while maintaining and improving indoor environmental conditions. This can be achieved through the use of computational intelligence and optimization. This research will evaluate model-based optimization processes (OP) for HVAC systems utilizing MATLAB, genetic algorithms and self-learning or self-tuning models (STM), which minimizes the error between measured and predicted performance data. The OP can be integrated into the EMCS to perform several intelligent functions achieving optimal system performance. The development of several self-learning HVAC …

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Faculty Publications

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo₂O_5+δ (PBCO) cathode with a nanowire current collector was reduced …

Modeling Of Chemical-Mechanical Couplings In Anode-Supported Solid Oxide Fuel Cells And Reliability Analysis, Xinfang Jin, Xingjian Xue

Faculty Publications

Oxygen ionic transport in conducting ceramics is an important mechanism enabling solid oxide fuel cell (SOFC) technology. The multi-physicochemical processes lead to the fact that the distribution of oxygen vacancy site fraction is not uniform in a positive-electrode electrolyte negative-electrode (PEN) assembly. Different oxygen vacancy concentrations induce different volumetric expansion of ceramics, resulting in complicated chemical–mechanical coupling phenomena and chemical stress in SOFCs. In this research, a mathematical model is developed to study oxygen ionic transport induced chemical stress in an SOFC. The model is validated using experimental polarization curves. Comprehensive simulations are performed to investigate chemical stress distribution in …

Energy Optimization Of A Free-Piston Enhanced Hybrid Vehicle, Kenneth Jarod Jones

Dissertations

The world’s heavy dependence on vehicles which utilize hydrocarbon fuels as a primary power source has renewed the interest in electric and hybrid vehicles for industrial, commercial, and public use. The primary objective of this movement is centered on increased efficiency in energy usage for transportation. Hybrid vehicles which utilize an internal combustion engine as a linear generator, converting energy stored in hydrocarbon fuels into electrical power, could serve as a transitioning technology. The free-piston enhanced hybrid vehicle (FPHV) could potentially fill this role. The present work contains a theoretical and numerical approach to analyzing and optimizing the usage of …

Out-Of-Step Detection Based On Zubov’S Approximation Boundary Method, Yawei Wei

Dissertations, Master's Theses and Master's Reports - Open

Disturbances in power systems may lead to electromagnetic transient oscillations due to mismatch of mechanical input power and electrical output power. Out-of-step conditions in power system are common after the disturbances where the continuous oscillations do not damp out and the system becomes unstable. Existing out-of-step detection methods are system specific as extensive off-line studies are required for setting of relays. Most of the existing algorithms also require network reduction techniques to apply in multi-machine power systems. To overcome these issues, this research applies Phasor Measurement Unit (PMU) data and Zubov’s approximation stability boundary method, which is a modification of …

Fault Location Algorithms, Observability And Optimality For Power Distribution Systems, Wanjing Xiu

Theses and Dissertations--Electrical and Computer Engineering

Power outages usually lead to customer complaints and revenue losses. Consequently, fast and accurate fault location on electric lines is needed so that repair work can be carried out as fast as possible.

Chapter 2 describes novel fault location algorithms for radial and non-radial ungrounded power distribution systems. For both types of systems, fault location approaches using line to neutral or line to line measurements are presented. It’s assumed that network structure and parameters are known, so that during-fault bus impedance matrix of the system can be derived. Functions of bus impedance matrix and available measurements at substation are formulated, …

Prediction Model To Estimate The Zero Crossing Point For Faulted Waveforms, Md. Shakawat Hossan

Theses and Dissertations--Electrical and Computer Engineering

In any power system, fault means abnormal flow of current. Insulation breakdown is the cause of fault generation. Different factors can cause the breakdown: Wires drifting together in the wind, Lightning ionizing air, wires with contacts of animals and plants, Salt spray or pollution on insulators. The common type of faults on a three phase system are single line-to-ground (SLG), Line-to-line faults (LL), double line-to-ground (DLG) faults, and balanced three phase faults. And these faults can be symmetrical (balanced) or Unsymmetrical (imbalanced).In this Study, a technique to predict the zero crossing point has been discussed and simulated. Zero crossing point …

Testing Of Two Novel Semi-Implicit Particle-In-Cell Techniques, Trenton J. Godar

Browse all Theses and Dissertations

PIC (Particle-in-cell) modeling is a computational technique which functions by advancing computer particles through a spatial grid consisting of cells, on which can be placed electric and magnetic fields. This method has proven useful for simulating a wide range of plasmas and excels at yielding accurate and detailed results such as particle number densities, particle energies, particle currents, and electric potentials. However, the detailed results of a PIC simulation come at a substantial cost of computational requirement and the algorithm can be susceptible to numerical instabilities. As processors become faster and contain more cores, the computational expense of PIC simulations …

Modeling And Validation Of A Synchronous-Machine/Controlled-Rectifier System, Kyle A. Hord

Theses and Dissertations--Electrical and Computer Engineering

The hardware validation of a novel average-value model (AVM) for the simulation of a synchronous-generator/controlled rectifier system is presented herein. The generator is characterized using genetic algorithm techniques to fit standstill frequency response (SSFR) measurements to q and d-axis equivalent circuits representing the generator in the rotor reference frame. The generator parameters form the basis of a detailed model of the system, from which algebraic functions defining the parametric AVM are derived. The average-value model is compared to the physical system for a variety of loading and operating conditions including step load change, change in delay angle, and external closed-loop …

Investigation Of Protection Issues And Method For The Distribution System With Distributed Generations, Ke Xu

Theses and Dissertations--Electrical and Computer Engineering

Because DGs are introduced into distribution systems, the coordination of fuses and reclosers doesn’t work well. It means the original protection schemes are not available for the distribution systems with DGs. This thesis paper presents the study on the impacts of DGs on the fault current and voltage in the distribution system by the simulation of a model distribution system. After we study the impacts of DG on distribution systems, there is an introduction of current several current protection schemes and fault locations methods. At last, an adaptive protection scheme with a more efficient fault location method for the distribution …

Multifrequency Averaging In Power Electronic Systems, Fei Pan

Theses and Dissertations--Electrical and Computer Engineering

Power electronic systems have been widely used in the electrical power processing for applications with power levels ranging from less than one watt in battery-operated portable devices to more than megawatts in the converters, inverters and rectifiers of the utility power systems. These systems typically involve the passive elements such as inductors, capacitors, and resistors, the switching electronic components such as IGBTs, MOSFETS, and diodes, and other electronic circuits. Multifrequency averaging is one of the widely used modeling and simulation techniques today for the analysis and design of power electronic systems. This technique is capable of providing the average behavior …