Electrical and Computer Engineering Commons^™

Grid Frequency And Voltage Support Using Pv Systems With Energy Storage, Ravi Bhatt, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

An optimized operating scheme for a utility connected community based photovoltaic (PV) system is described. the system can participate in grid ancillary services like frequency and voltage regulation functions based on the Smart Grid framework. the proposed model comprises of a PV plant with Li-ion batteries coupled to the grid with the help of a three-phase inverter. a two-way communication between the PV plant and the grid is assumed. the PV/storage plant provides constant updates on its current kW/kVar capability, and the grid transmits the demand for specific amounts of power and for specific lengths of time. the battery charging …

Investment Payback Calculator For Distributed Generation Sources, Md Rasheduzzaman, Elizabeth Stahlman, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

The development of a distributed generation payback calculator that can be used for different types of energy technologies such as small wind turbines, fuel cells, microturbines, solar PV and other technologies is presented. the payback calculator takes several inputs such as technology costs, expected life of the project, capacity factor, system size, customer type, and several other relevant parameters. from these inputs, the calculator computes several different outputs including the total energy produced within a year, the rate of return, total expenses, total cash flow, and the discounted payback period in years. the calculator is embedded into a website available …

Analysis Of Unbalanced System Efficiency With A Positive Sequence Power Flow Program, Karl Stefanski, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Most existing power flow programs assume balanced loading where the positive sequence impedances are sufficient to use. However, a more accurate approach is often required due to the increasing penetration of single-phase distributed generation sources on distribution grids which tend to introduce large imbalances. the proposed method uses a positive sequence power flow algorithm where the inputs are modified to accurately simulate an unbalanced system. the algorithm is tested on the IEEE 4-bus system and the results compared with published results. the impact of the analysis on system efficiency calculations are shown for the 4-bus system as well as for …

Compressed Sensing Based Analytical Modeling For Through-Silicon-Via Pairs, Tao Wang, Jingook Kim, Jun Fan, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Through-Silicon-Vias (TSVs) are the critical enabling technique for three-dimensional integrated circuits (3D ICs). While there are a few existing works in literature to model the electrical performance of TSVs, they are either for fixed geometry or in lack of accuracy. in this paper, we use compressed sensing technique to model the electrical performance of TSV pairs. Experimental results indicate that with an exceptionally small number of samples, our model has a maximum relative error of 3.94% compared with full-wave simulations over a wide range of geometry parameters and frequencies. © 2011 IEEE.

Three-Dimensional Polarization States Of Monochromatic Light Fields, R. M.A. Azzam

Electrical Engineering Faculty Publications

The 3×1 generalized Jones vectors (GJVs) [ExEyEz]t (t indicates the transpose) that describe the linear, circular, and elliptical polarization states of an arbitrary three-dimensional (3-D) monochromatic light field are determined in terms of the geometrical parameters of the 3-D vibration of the time-harmonic electric field. In three dimensions, there are as many distinct linear polarization states as there are points on the surface of a hemisphere, and the number of distinct 3-D circular polarization states equals that of all two-dimensional (2-D) polarization states on the Poincaré sphere, of which only two are circular states. The subset of 3-D polarization …

Electrostatically Tunable Meta-Atoms Integrated With In Situ Fabricated Mems Cantilever Beam Arrays, Ronald A. Coutu Jr., Peter J. Collins, Elizabeth A. Moore, Derrick Langley, Matthew E. Jussaume, Lavern A. Starman

Electrical and Computer Engineering Faculty Research and Publications

Two concentric split ring resonators (SRRs) or meta-atoms designed to have a resonant frequency of 14 GHz are integrated with microelectromechanical systems cantilever arrays to enable electrostatic tuning of the resonant frequency. The entire structure was fabricated monolithically to improve scalability and minimize losses from externally wire-bonded components. A cantilever array was fabricated in the gap of both the inner and outer SRRs and consisted of five evenly spaced beams with lengths ranging from 300 to 400 μm. The cantilevers pulled in between 15 and 24 V depending on the beam geometry. Each pulled-in beam increased the SRR gap capacitance …

Introducing Porous Silicon As A Sacrificial Material To Obtain Cavities In Substrate Of Soi Wafers And A Getter Material For Mems Devices, Wajihuddin Mohammad

Doctoral Dissertations

Microelectromechanical system (MEMS) resonators have been a subject of research for more than four decades. The reason is the huge potential they possess for frequency applications. The use of a MEMS resonator as the timing element has an experimental history and huge progress has been made in this direction. Vacuum encapsulated MEMS resonators are required for high precision frequency control. Hence, a device with a high quality factor and durability is needed. In this effort, a new process for producing a cavity in the substrate of Silicon on insulator (SOI) MEMS devices and augmenting it with a getter using porous …

Development And Prototyping Of A Ground Fault Circuit Interrupter For 3-Phase 480 Volt Systems, Matthew R. Norlander

Master's Theses

Ground Fault Circuit Interrupter (GFCI) technology was first introduced in the NEC in 1971, yet four decades later the technology has not been introduced to a great extent outside of the home environment. This thesis introduces the difficulties encountered in low-voltage three phase ground fault current detection, and adopts a previously patented tripping scheme to develop and prototype a digital relay for 3-phase 480 volt systems capable of the sensitivity and speed required for personnel safety. Results demonstrate the feasibility of the concept and suggest commercial development should be pursued. The prototype is capable of mA sensitivity and reliably detects …

Passive Micromixers And Organic Electrochemical Transistors For Biosensor Applications, Senaka Krishna Kanakamedala

Doctoral Dissertations

Fluid handling at the microscale has greatly affected different fields such as biomedical, pharmaceutical, biochemical engineering and environmental monitoring due to its reduced reagent consumption, portability, high throughput, lower hardware cost and shorter analysis time compared to large devices. The challenges associated with mixing of fluids in microscale enabled us in designing, simulating, fabricating and characterizing various micromixers on silicon and flexible polyester substrates. The mixing efficiency was evaluated by injecting the fluids through the two inlets and collecting the sample at outlet. The images collected from the microscope were analyzed, and the absorbance of the color product at the …

Modification Of Digital Music Files For Use In Human Temporary Threshold Shift Studies, C. G. Le Prell, Q. Yang, J. G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

An exposure that is reproducible across clinical/laboratory environments, and appealing to subjects, is described here. Digital music files are level-equated within and across songs such that playlists deliver an exposure that is consistent across time. Modified music is more pleasant to listen to than pure tones or shaped noise and closely follows music exposures subjects may normally experience. Multiple therapeutics reduce noise-induced hearing loss in animals, but human trial design is complicated by limited access to noise-exposed subject populations. The development of standard music exposure parameters for temporary threshold shift studies would allow comparison of protection across agents with real-world …

Isotope Identification And Source Directional Determination Using Gamma Radiation Profiling, Christopher L. Schrage

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This thesis presents a method for evaluating gamma radiation profiles using a low power gamma radiation detector system (GRDS). This method enables multiple radioactive gamma isotopes to be identified and determine the respective vector directions of those sources relative to the GRDS location. This detection method must be accurate, implemented as a handheld or fixed solution, and have a suitable battery life for a variety of industrial needs.

This paper will first explain the low power GRDS that was used for developing these detection methods. The target gamma isotopes that are used for validating these methods will be described along …

Disaggregating Time Series Data For Energy Consumption By Aggregate And Individual Customer, Steven Vitullo

Dissertations (1934 -)

This dissertation generalizes the problem of disaggregating time series data and describes the disaggregation problem as a mathematical inverse problem that breaks up aggregated (measured) time series data that is accumulated over an interval and estimates its component parts.

We describe five different algorithms for disaggregating time series data: the Naive, Time Series Reconstruction (TSR), Piecewise Linear Optimization (PLO), Time Series Reconstruction with Resampling (RS), and Interpolation (INT). The TSR uses least squares and domain knowledge of underlying correlated variables to generate underlying estimates and handles arbitrarily aggregated time steps and non-uniformly aggregated time steps. The PLO performs an adjustment …

Analysis Of An Air-Spaced Patch Antenna Near 1800 Mhz, Hermine Nathalie Akouemo Kengmo Kenfack

Master's Theses (2009 -)

Microstrip antennas are a type of printed antenna which consists of a patch on top of a grounded substrate. A major limitation for the performance of the patch antenna is the dielectric substrate. The idea of using air as dielectric was therefore considered to overcome that limitation because air has the lowest permittivity and no loss. The goal of this work is to build an air-spaced patch antenna, with the minimum resonant frequency at 1800 MHz and with a return loss of at least 10 dB.

This work is novel because the air-spaced patch antenna has not been extensively studied. …

Stability And Minimum Cost Analysis Of A Discrete-Time Disturbance Accommodation Controller, Katrina H. Barhouse

Master's Theses (2009 -)

Disturbance accommodation control (DAC) is a method for designing a controller that minimizes the effects of disturbances of known waveform type, but with unknown arrival time, duration or magnitude. Systems that do not have a control term in the measurement equation pose a particular challenge for DAC design. A disturbance accommodation controller for these types of systems was previously developed by defining a pseudo-output consisting of the current output and previous control input terms with weighting coefficients.

The objective of the present work is to analyze the stability and performance of the discrete- time disturbance accommodation controller for systems without …

Fpga Bootstrapping Using Partial Reconfiguration, Patrick Sutton Ostler

Theses and Dissertations

Partial reconfiguration (PR) is the process of configuring a subset of resources on a Field Programmable Gate Array (FPGA) while the remainder of the device continues to operate. PR extends the usability of FPGAs and makes it possible to perform design bootstrapping. Just like bootstrapping in PCs, bootstrapping in FPGAs consists of using a small application to initialize basic services and load a larger, more complex application to the device. Bootstrapping allows for unique design applications that can be used to maintain communication services, increase design security, reduce initial configuration time, and reduce nonvolatile configuration memory storage. This thesis presents …

Cooperative Approaches Indicating To Capacity And Power Control For Ad Hoc Wireless Network, Liuju Wu, Maciej Jan Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, two integrated schemes for fair capacity allocation and power control for ad hoc wireless network are presented. the game theory approach is utilized to derive a collaborative update law. in the practical wireless network, a non-uniform distribution of nodes results in varying degree of interference among the network links or hops. Such varying mutual interference may lead to unfair allocation of bandwidth and result in network congestion. as a result, some links may become bottlenecks for the entire network. Hence, it is important to fairly allocate resources in the entire network. the proposed schemes aim to address …

Efficient Design And Synthesis Of Decimation Filters For Wideband Delta-Sigma Adcs, Rajaram Mohan Roy Koppula, Sakkarapani Balagopal, Vishal Saxena

Electrical and Computer Engineering Faculty Publications and Presentations

A design methodology for synthesizing power-optimized decimation filters for wideband Delta Sigma (ΔΣ) analog-to-digital converters (ADCs) for next-generation wireless standards is presented. The decimation filter is designed to filter the out-of-band quantization noise from a fifth-order continuous-time ΔΣ modulator, with 20 MHz signal bandwidth and 14-bits resolution. The modulator employs an oversampling ratio (OSR) of 16 with a clock rate of 640 MHz. Retiming, pipelining, Canonical Signed Digits (CSD) encoding has been utilized along with an optimized halfband filter to realize the power savings in the overall decimation filter. A process flow to rapidly design the optimized filters in MATLAB, …

Theoretical Capacity Analysis For Multi-Hop Backscatter Communication Networks, Aditya V. Padaki, Maciej J. Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Traditionally wireless sensor networks (WSNs) employ active RF communication where the RF signal has to be generated at nodes, thus consuming a significant amount of energy. in contrast, employment of passive communication, where nodes backscatter a modulated version of the incident RF signal, offers great advantages including reducing the energy cost of communication. Existing example includes a traditional RFID system with active reader communicating directly with passive tags. However, the proposed approach targets future, more advanced systems that support a generic backscatter communication. However, the inherent asymmetry in communication, reliance on external source of RF signal, and limited energy storage …

Adaptive Control In Swarm Robotic Systems, Hanyi Dai

The Hilltop Review

Inspired by the collective behavior observed in natural insects, swarm robotics is a new approach in designing control algorithms for a large group of robots performing a certain task. In such robotic systems, an individual robot with only limited capabilities in terms of sensing, computation, and communication can adapt its own behavior so that a desired collective behavior emerges from the local interactions among robots and between robots and the environment. Swarm robotics has been the focus of increased attention recently because of the beneficial features demonstrated in such systems, such as higher group efficiency, robustness against the failures of …

The Effects Of Mental Training On Brain Computer Interface Performance With Distractions, John Larocco

Theses and Dissertations

The overall success of a brain computer interface (BCI) is largely dependent on the features used to make decisions. Noise in the electroencephalography (EEG) increases the difficulty of acquiring meaningful features. Previous literature suggests teaching subjects meditation and relaxation techniques may improve features relevant to BCI operation. The purpose of this study was to investigate performance on several cognitive protocols for both individuals who use meditation techniques and those who do not use these techniques. Both groups were given a motor imagery based BCI protocol, a P300 speller BCI, a verbal learning task, and an N-back test. No significant difference …