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Short-Term Load Forecasting Using Neural Network For Future Smart Grid Application, Jixuan Zheng 2014 University of Denver

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 2014 Michigan Technological University

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 2014 University of Denver

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 …


Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera 2014 North Carolina Agricultural and Technical State University

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 2014 North Carolina Agricultural and Technical State University

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 …


Modeling Of Chemical-Mechanical Couplings In Anode-Supported Solid Oxide Fuel Cells And Reliability Analysis, Xinfang Jin, Xingjian Xue 2014 University of South Carolina - Columbia

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 2014 North Carolina Agricultural and Technical State University

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 …


Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Wolf, Kristofor R. Brye 2014 University of Arkansas, Fayetteville

Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Wolf, Kristofor R. Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Hydraulic fracturing is the process of injecting aqueous solutions at high pressure to break apart rock formations and increase the extraction of natural gas. The solutions are recovered and have been land-applied as one disposal technique. Excessive fluid application can result in increased soil salinity that can inhibit plant growth. The objective of this greenhouse study was to evaluate the effects of inorganic fertilizer, broiler litter, and Milorganite® and soil depth interval (0-15 cm or 0-30 cm) on the growth of bermudagrass [Cynodon dactylon (L.) Pers] in soil that was collected from a site that had been contaminated with fracturing …


Fault Location Algorithms, Observability And Optimality For Power Distribution Systems, Wanjing Xiu 2014 University of Kentucky

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 2014 University of Kentucky

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 …


Dilute-Acid-Extractable Phosphorus, Arsenic, And Selenium In Weathered And Fresh Coal Fly Ash, Chris Wilbanks, Kristofor Brye, David Miller 2014 University of Arkansas, Fayetteville

Dilute-Acid-Extractable Phosphorus, Arsenic, And Selenium In Weathered And Fresh Coal Fly Ash, Chris Wilbanks, Kristofor Brye, David Miller

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Fly ash is a byproduct of the combustion of coal, primarily by coal-fired power plants. Over 97.8 million tonnes of fly ash are produced each year in the United States. Fly ash can contain trace elements in concentrations that can cause health risks. Recent spills have highlighted that fly ash disposal is problematic. The objective of this study was to evaluate the effects of fly-ash type (fresh and weathered) from a local coal-burning power plant and extraction time (2 and 6 h) on dilute-acid extractable concentrations of phosphorus (P), arsenic (As), and selenium (Se). Ash samples were extracted with 0.1 …


Out-Of-Step Detection Based On Zubov’S Approximation Boundary Method, Yawei Wei 2014 Michigan Technological University

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 …


Hydrothermal Processing Of Biomass For Biofuels, Sandeep Kumar 2014 Old Dominion University

Hydrothermal Processing Of Biomass For Biofuels, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

[First paragraph] In recent years, significant research interests have been placed on the conversion of non-food biomass resources such as lignocellulosic biomass (terrestrial) and algae (aquatic) to biofuels. Among all the alternative or renewable energy options, biomass is the only resource which is carbon neutral and can potentially replace part of fossil fuels use as liquid transportation fuels as well as contribute to electricity generation. Therefore, it can play a significant role in partially replacing oil, natural gas, and coal utilization for heat and energy generation. However, high moisture content of fresh biomass or algae is one of the major …


Testing Of Two Novel Semi-Implicit Particle-In-Cell Techniques, Trenton J. Godar 2014 Wright State University

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 …


A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue 2014 University of South Carolina - Columbia

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 PrBaCo2O5+δ (PBCO) cathode with a nanowire current collector was reduced …


Modeling And Validation Of A Synchronous-Machine/Controlled-Rectifier System, Kyle A. Hord 2014 University of Kentucky

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 2014 University of Kentucky

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 2014 University of Kentucky

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 …


A New Design Of Dc-Dc Converter For Capacitive Deionization Process, Zhiao Li 2014 University of Kentucky

A New Design Of Dc-Dc Converter For Capacitive Deionization Process, Zhiao Li

Theses and Dissertations--Electrical and Computer Engineering

The shortage of clean water has become a significant global problem, and capacitive deionization (CDI) is a technology that can be used to help relieve the problem. A Ćuk converter system that can recover energy from CDI cells is described. This converter transfers energy between two CDI cells when a cell is in its desorption period, allowing energy that would otherwise be lost to be recovered and improving overall system efficiency. In order to control the states of the MOSFET switches in the converter, a self boost charge pump is used. In this way, the microcontroller can control system duty …


Coordinated Voltage And Reactive Power Control Of Power Distribution Systems With Distributed Generation, Esa A. Paaso 2014 University of Kentucky

Coordinated Voltage And Reactive Power Control Of Power Distribution Systems With Distributed Generation, Esa A. Paaso

Theses and Dissertations--Electrical and Computer Engineering

Distribution system voltage and VAR control (VVC) is a technique that combines conservation voltage reduction and reactive power compensation to operate a distribution system at its optimal conditions. Coordinated VVC can provide major economic benefits for distribution utilities. Incorporating distributed generation (DG) to VVC can improve the system efficiency and reliability. The first part of this dissertation introduces a direct optimization formulation for VVC with DG. The control is formulated as a mixed integer non-linear programming (MINLP) problem. The formulation is based on a three-phase power flow with accurate component models. The VVC problem is solved with a state of …


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