Electrical and Electronics Commons^™

Use Of Digital Twins To Mitigate Communication Failures In Microgrids, Andrew Eggebeen

Theses and Dissertations

This work investigates digital twin (DT) applications for electric power system (EPS) resilience. A novel DT architecture is proposed consisting of a physical twin, a virtual twin, an intelligent agent, and data communications. Requirements for the virtual twin are identified. Guidelines are provided for generating, capturing, and storing data to train the intelligent agent. The relationship between the DT development process and an existing controller hardware-in-the-loop (CHIL) process is discussed. To demonstrate the proposed DT architecture and development process, a DT for a battery energy storage system (BESS) is created based on the simulation of an industrial nanogrid. The creation …

A Design Strategy To Improve Machine Learning Resiliency Of Physically Unclonable Functions Using Modulus Process, Yuqiu Jiang

Theses and Dissertations

Physically unclonable functions (PUFs) are hardware security primitives that utilize non-reproducible manufacturing variations to provide device-specific challenge-response pairs (CRPs). Such primitives are desirable for applications such as communication and intellectual property protection. PUFs have been gaining considerable interest from both the academic and industrial communities because of their simplicity and stability. However, many recent studies have exposed PUFs to machine-learning (ML) modeling attacks. To improve the resilience of a system to general ML attacks instead of a specific ML technique, a common solution is to improve the complexity of the system. Structures, such as XOR-PUFs, can significantly increase the nonlinearity …

Characterization, Simulation, And Test Method For Image Artifacts Due To Phase Drift Of The Saw Filter In The Magnetic Resonance Receiver, Gabriel T. Jacobs

Theses and Dissertations

The receiver for a Magnetic Resonance (MR) scanner is responsible for capturing the precise frequency and phase of extremely low-power RF signals emanating from the human body; and consequentially must minimize unexpected phase drift in the received signal. One well-known source for temperature-dependent phase drift in RF electronics is the Surface Acoustic Wave (SAW) filter. In this work, the phase drift due to temperature changes in the SAW filter of an MR receiver was evaluated for its potential effects on image quality using several image quality metrics. A lab bench method was developed to playback MR images using typical lab-equipment …

Ultra Fast Dc Switch, Ian A. Buck

Theses and Dissertations

With advancements in power electronics, DC power systems are a strong contender forfuture power system and shipboard application studies. However, to ensure proper DC power systems, protection engineers must develop different DC protection schemes to maintain proper system protection levels. The critical issue behind developing DC protection devices is that the signal never crosses zero naturally, as in AC circuit breakers and AC disconnect switches. There is also a necessity for galvanic isolation in the DC protection system. A method developed is pairing a mechanical commercial-off-the-shelf vacuum interrupter, a Thomson coil actuator, and a current commutating drive circuit (CCDC). The …

Applications Of Surface Discharge Modeling, Simulation And Testing To Electrical Insulation Systems, Skyler Schwartz

Theses and Dissertations

Advances in power electronics and the increasing demand for highly power dense power distributionsystems have increased the demands for electrical insulation systems. A critical challenge in insulation system design is the prevention and mitigation of partial discharge which drives premature aging and failure of electrical assets. This work applies and validates a recently proposed model for surface discharge applied to the case of a laminated bus bar. The results from the modeling and testing shows the traditional concept of creepage, while essential for preventing a flashover events provides little insight into surface discharge. The approach to characterize the laminated bus …

Allocation And Compilation Methodology For Modular Power Electronic Equipment Metamodels, William J. Koebel

Theses and Dissertations

With the ongoing electrification of Navy vessels motivated by increased power demands, evolving operating environments, and more stringent pollution policies, modular distribution networks have been proposed to introduce survivability, affordability, and resiliency into future ship designs. A virtual prototyping process (VPP) has been introduced to produce scalable metamodels for the Leading Edge Architecture for Prototyping Systems (LEAPS) database that enables development of modular distribution networks on the U.S. Navy’s Smart Ship System Design (S3D) design platform. This work proposes an allocation and compilation methodology for use in the VPP that modularizes enabling technologies for integration into a modular distribution network …

High Power, Medium Frequency, And Medium Voltage Transformer Design And Implementation, Ahmad El Shafei

Theses and Dissertations

Many industrial applications that require high-power and high-voltage DC-DC conversion are emerging. Space-borne and off-shore wind farms, fleet fast electric vehicle charging stations, large data centers, and smart distribution systems are among the applications. Solid State Transformer (SST) is a promising concept for addressing these emerging applications. It replaces the traditional Low Frequency Transformer (LFT) while offering many advanced features such as VAR compensation, voltage regulation, fault isolation, and DC connectivity. Many technical challenges related to high voltage stress, efficiency, reliability, protection, and insulation must be addressed before the technology is ready for commercial deployment. Among the major challenges in …

Modeling And Validation Of Common-Mode Emission In Silicon Carbide Based Voltage Source Converters, Tianchen Li

Theses and Dissertations

Electromagnetic compatibility (EMC) issues have become one of the most difficult challenges in power converter designs. With the invention of wide bandgap (WBG) power semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) power MOSFETs, the power converter designs are provided with the potential to be significantly more power dense than older generation converters using silicone IGBTs. However, the majority of spectral contents of the switching waveforms are moved from the very-low-frequency (VLF, 3 kHz to 30 kHz) range to low-frequency and up to the very-high-frequency (VHF, 30 MHz to 300 MHz) range. Moreover, due to the design traits …

Nonreciprocal Surface Waves On Gyrotropic Interfaces, Alexander Martin Holmes

Theses and Dissertations

In this dissertation, the properties of highly nonreciprocal (unidirectional) surface waves guided along the interface between free-space and various 2D and 3D gyrotropic continua are investigated using analytic, numerical, and experimental methods. From a classical electromagnetics perspective, nonreciprocity in the dispersion of surface wave modes supported by the interface is achieved by breaking both time-reversal and space-inversion symmetries in the collective response of the waveguide, which consists of the two interfaced materials. More recently, however, a connection to momentum space topology via the bulk-edge correspondence principle has been made for gyrotropic continua, providing additional insights into the underlying physics that …

Applications Of Machine Learning In Medical Prognosis Using Electronic Medical Records, Farnaz Hajiahmadifoomani

Theses and Dissertations

Approximately 84 % of hospitals are adopting electronic medical records (EMR) In the United States. EMR is a vital resource to help clinicians diagnose the onset or predict the future condition of a specific disease. With machine learning advances, many research projects attempt to extract medically relevant and actionable data from massive EMR databases using machine learning algorithms. However, collecting patients' prognosis factors from Electronic EMR is challenging due to privacy, sensitivity, and confidentiality. In this study, we developed medical generative adversarial networks (GANs) to generate synthetic EMR prognosis factors using minimal information collected during routine care in specialized healthcare …

Nonreciprocal Electromagnetics Of Layered Media, Samaneh Pakniyat

Theses and Dissertations

In plasmonic systems, interaction of light and surface plasmons leads to excitation of surface plasmon polaritons (SPPs) carrying energy on the surface. In an isotropic plasmonic system, the SPPs optical response is reciprocal, which means that the forward and backward surface waves have identical propagation behaviors and SPPs refract when they encounter a discontinuity on the surface. In order to excite SPPs resilient to the surface disorders, the system reciprocity needs to be broken by different techniques such as applying an external magnetic bias. In this case, the plasmonic system becomes a gyrotropic medium. Recently, it has been shown that …

Age-Of-Information-Aware Load Frequency Control And Stability Analysis, Dan Jiao

Theses and Dissertations

Nowadays, modern load frequency control (LFC) systems employ an open communication system, which causes information staleness inevitably to arise. This issue can degrade the regulation performance of LFC and even threaten stability. This thesis introduces age-of-information (AoI) into LFC to describe the information freshness at the control center. Unlike communication delay, AoI can provide real-time information state based on information update rate. In this thesis, a muti-area LFC-AoI model is built to evaluate the update rate effect on LFC performance. Then, an AoI-based stability criterion for discrete LFC systems is built. After that, the AoI margin is proposed and compared …

Potential Of Grid-Scale Pv And Storage Facilities To Participate In Capacity Markets, Nicholas Giovannetti

Theses and Dissertations

The recent FERC Order 841 has provided an opportunity for grid-scale PV and battery facilities to participate in the capacity market providing ancillary services. Order 841 combined with steadily decreasing PVand battery costs and increasing demand for renewable energy, gives high potential for a PV and battery facility to be economically viable. In this study, an analysis tool is developed as an auxiliary to the PV + Storage + Control + Grid (PSCG) simulation to estimate the megawatts (MW) of dispatchable capacity that can be reliably offered by a PV and storage facility. Limits are based on grid connection, power …

Stability Analysis And Parameters Design Of The Voltage Source Inverter With Lc Filter, Hongzhen Zhang

Theses and Dissertations

Voltage source inverters (VSI) are widely used in many applications. In this thesis, the stability of the LC-type single-phase off-grid inverter is investigated and the emphasis is focused on how to extend the effective damping region. The harmonics resonance is the main factor affecting the stability of the system. To deal with this problem, the stability of the system with passive damping is investigated. Aiming at the problem that passive damping methods introduce power loss, Active damping methods are proposed. Considering the system with traditional inductor current feedback active damping cannot be stable when resonance frequency is close to fs/6, …

Model Predictive Control For Grid Scale Pv And Battery, Sahithi Chatradi

Theses and Dissertations

Model Predictive Control (MPC) is a control technique that uses prediction data to optimize costs over a given predictive horizon. There are many papers that use this technique to optimize cost in a substantially loaded microgrid, but these techniques are not feasible for utility-scale PV+Storage facility. In this study, MPC is used to optimize the cost for a utility-scale PV+Storage facility, by adding a factor of a possible curtailment. The thesis also presents the various factors that the MPC has in that utility size grid. These factors include line losses, net yield, and curtailment.

Compact Field Programmable Gate Array Based Physical Unclonable Functions Circuits, Yangpingqing Hu

Theses and Dissertations

The Physical Unclonable Functions (PUFs) is a candidate to provide a secure solid root source for identification and authentication applications. It is precious for FPGA-based systems, as FPGA designs are vulnerable to IP thefts and cloning. Ideally, the PUFs should have strong random variations from one chip to another, and thus each PUF is unique and hard to replicate. Also, the PUFs should be stable over time so that the same challenge bits always yield the same result. Correspondingly, one of the major challenges for FPGA-based PUFs is the difficulty of avoiding systematic bias in the integrated circuits but also …

Experimental Comparison Of Load Sharing Techniques For Fast Motion In Industrial Machines, Eike Marten Hillrichs

Theses and Dissertations

Load sharing and synchronization techniques are essential for modern automation applications where single motor systems cannot meet the application requirements. Evenly sharing the load between multiple motors can increase the output of processes and reduce maintenance efforts due to uneven wear and tear. Rockwell Automation has developed two load sharing techniques for fast motion control applications. In this Thesis, the two load sharing techniques are experimentally compared regarding their ability to evenly share loads and control synchronized motions in a multi motor setup for fast motion. The techniques are compared using a setup with two motors coupled by a timing …

Common-Mode Modeling Of Neutral Point Clamped Converter Based Dual Active Bridge, Ryan James Olson

Theses and Dissertations

Modern power converters designed with wide-bandgap semiconductors are known to generate substantial conducted electromagnetic interference as a side effect of high edge rate and high frequency switching. With the advancement in power electronic converters, the significant EMI challenges need to be addressed for distribution level power systems. The goal is to provide a computationally efficient method of EMI characterization for conducted emissions for this future generation of power distribution systems. The first step in making this possible is through creating an accurate EMI characterization platform for the neutral point clamped dual active bridge. In this thesis, a formalized common-mode modeling …

An Insurance Framework For Cyber-Physical Power Systems Considering Integrated Cybersecurity-Reliability Assessment, Pikkin Lau

Theses and Dissertations

Due to the development of cyber-physical systems for modernizing power grids, vulnerabilityassessment has become an emerging focus in power system security studies. With the increasing application of cyber-enabled technologies in power systems, modern power system is prevalently exposed to a wide gamut of cybersecurity threats. In this dissertation, the power supply reliability is evaluated considering the strategic allocation of defense resources and smart technologies. The optimal mixed strategies are formulated by the Stackelberg Security Game to allocate the defense resources on multiple targets subject to cyberattacks. Smart monitoring with preventive and corrective measures is able to boost the substation availability …

Advanced Analytics In Smart Manufacturing: Anomaly Detection Using Machine Learning Algorithms And Parallel Machine Scheduling Using A Genetic Algorithm, Meiling He

Theses and Dissertations

Industry 4.0 offers great opportunities to utilize advanced data processing tools by generating Big Data from a more connected and efficient data collection system. Making good use of data processing technologies, such as machine learning and optimization algorithms, will significantly contribute to better quality control, automation, and job scheduling in Smart Manufacturing. This research aims to develop a new machine learning algorithm for solving highly imbalanced data processing problems, implement both supervised and unsupervised machine learning auto-selection frameworks for detecting anomalies in smart manufacturing, and develop a genetic algorithm for optimizing job schedules on unrelated parallel machines. This research also …

A Deep Recurrent Neural Network With Iterative Optimization For Inverse Image Processing Applications, Masaki Ikuta

Theses and Dissertations

Many algorithms and methods have been proposed for inverse image processing applications, such as super-resolution, image de-noising, and image reconstruction, particularly with the recent surge of interest in machine learning and deep learning methods.

As for Computed Tomography (CT) image reconstruction, the most recently proposed methods are limited to image domain processing, where deep learning is used to learn the mapping between a true image data set and a noisy image data set in the image domain. While deep learning-based methods can produce higher quality images than conventional model-based algorithms, these methods have a limitation. Deep learning-based methods used in …

Design, Control, And Development Of A Multilevel Converter Medium Voltage Ac To Low Voltage Dc For Fleet Electric Vehicle Charge Station, Garry Jean-Pierre

Theses and Dissertations

There is a shift in the technology of vehicles from gas and diesel engines to electric vehicles(EVs). Approximately ten million EVs were available globally in 2020 and it is projected that number will reach 145 million by 2030. To power the increasing number of EVs, the number of EV charging stations is growing at a significant rate. In order to provide flexibility and longer driving ranges to customers, the trend is to install DC fast charging stations. These chargers demand high power at low voltage, which our existing electrical distribution system cannot accommodate without major upgrades. Currently, bulky transformers are …

A High-Bandwidth, Spectrally Broad Photodetector Based On Optically-Induced Seebeck Effect, Niloufar Yavarishad

Theses and Dissertations

In this thesis, we engineered a fast response high bandwidth self-powered infrared photodetector based on optically induced Seebeck effect in Cd3As2 operating at room temperature. The metal-semimetal-metal device was subject to transient photo-response tests using high-frequency lock-in modulation techniques. Our photodetector demonstrates a Seebeck voltage under the off-center illumination of a laser with the wavelength of 1064 nm, due to a temperature gradient. The photocurrent is readily registered at a modulation frequency of 6 kHz and further analysis indicates the sensor intrinsic bandwidth is predicted to approach the terahertz range. The responsivity of the sensor is 0.27 mA/W at room …

Electrospinning Processing Techniques For The Manufacturing Of Composite Dielectric Elastomer Fibers, Rani Elhajjar

Civil and Environmental Engineering Faculty Articles

Dielectric elastomers (DE) are novel composite architectures capable of large actuation strains and the ability to be formed into a variety of actuator configurations. However, the high voltage requirement of DE actuators limits their applications for a variety of applications. Fiber actuators composed of DE fibers are particularly attractive as they can be formed into artificial muscle architectures. The interest in manufacturing micro or nanoscale DE fibers is increasing due to the possible applications in tissue engineering, filtration, drug delivery, catalysis, protective textiles, and sensors. Drawing, self-assembly, template-direct synthesis, and electrospinning processing have been explored to manufacture these fibers. Electrospinning …

Transport, Photoluminescence & Photoconduction Characteristics Of Free Standing Two-Dimensional Γ-Alumina & Titanium Superlattice Doped Two-Dimensional Γ-Alumina Grown By Graphene-Assisted Atomic Layer Deposition, Elaheh Kheirandish

Theses and Dissertations

This study presents a facile high-yield bottom-up fabrication, morphology, crystallographic and optoelectronic characterization of free-standing quasi-2D γ-alumina, a non van der Waals 2D material. The synthesis comprises a multi-cycle atomic layer deposition (ALD) of amorphous alumina on a porous interconnected graphene foam as a growth scaffold and removed next by annealing and sintering the alumina/graphene/alumina sandwich at ~ 800 °C in air . The crystallographic and structural characteristics of the formed non-van der Waals quasi 2D γ-alumina were studied by X-ray diffraction (XRD), selected area electron diffraction (SAED), and high-resolution transmission electron microscopy (HRTEM). This analysis revealed the synthesized 2D …

Wound Image Classification Using Deep Convolutional Neural Networks, Behrouz Rostami

Theses and Dissertations

Artificial Intelligence (AI) includes subfields like Machine Learning (ML) and DeepLearning (DL) and discusses intelligent systems that mimic human behaviors. ML has been used in a wide range of fields. Particularly in the healthcare domain, medical images often need to be carefully processed via such operations as classification and segmentation. Unlike traditional ML methods, DL algorithms are based on deep neural networks that are trained on a large amount of labeled data to extract features without human intervention. DL algorithms have become popular and powerful in classifying and segmenting medical images in recent years. In this thesis, we shall study …

Real Time License Plate Detection Based On Machine Learning, Yu-Liang Chiang

Theses and Dissertations

License Plate Recognition (LPR) is a very useful technology skill for our world, and also includes a wide range of applications. During my student life in the US, it is not common to see this kind of technology applied in the public parking lot. LPR has been researched for many years in Asia. There are a lot of LPR systems, which include different types of technologies, being used in Taiwan. In my point of view, those systems are still using the conventional technology, which does not involve artificial intelligence. In many applications, that makes it possible to make mistakes in …

Modular Multilevel Converters With Module-Level Energy Storage For Medium Voltage Applications, Bora Novakovic

Theses and Dissertations

This dissertation is on Modular Multilevel Converter (MMC) converter design and analysis and its integration with energy storage at the low voltage module-level. The developed converter concept and topology can be used in various applications especially for the support of intermittent renewable energy resources. The general converter structure is analyzed and extended to include integrated energy storage suitable but not limited to medium voltage applications. The behavior of the idealized structure is analyzed to obtain equations that govern general converter behavior and identify possible control loops. Detail mathematical switching model is developed for the MMC converter with generalized module structure. …

Design And Optimization Of A Modular Dc-Dc Power Converter For Medium Voltage Shipboard Applications, Seyed Rasoul Hosseini

Theses and Dissertations

Power electronic converters rated for medium voltage direct current (MVDC) are promising for electrification of future ships. In shipboard electrification, due to limitation of space, energy and technical maintenance, the high-power density, high efficiency and modularity of the power electronic converters are desired. Utilizing power modules made from wide band gap (WBG) semiconductors like silicon carbide (SiC) and high frequency power transformer (HFPT) can be beneficial for obtaining the high-power density, high efficiency and isolation that is required for the power electronic converters. To provide power for the low voltage (LV) DC loads, a conversion of the power from MVDC …

Characterization Of Fiber Bragg Grating Based, Geometry-Dependent, Magnetostrictive Composite Sensors, Edward Lynch

Theses and Dissertations

Optical sensors based on geometry dependent magnetostrictive composite, having potential applications in current sensing and magnetic field sensing are modeled and evaluated experimentally with an emphasis on their thermal immunity from thermal disturbances. Two sensor geometries composed of a fiber Bragg grating (FBG) embedded in a shaped Terfenol-D/epoxy composite material, which were previously prototyped and tested for magnetic field response, were investigated. When sensing magnetic fields or currents, the primary function of the magnetostrictive composite geometry is to modulate the magnetic flux such that a magnetostrictive strain gradient is induced on the embedded FBG. Simulations and thermal experiments reveal the …