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Full-Text Articles in Engineering

Aggregated Der Management In Advanced Distribution Grids, Mohsen Mahoor Jan 2020

Aggregated Der Management In Advanced Distribution Grids, Mohsen Mahoor

Electronic Theses and Dissertations

Evolution of modern power systems are more distinct in distribution grids, where the growing integration of microgrids as well as distributed energy resources (DERs), including renewable energy resources, electric vehicles (EVs), and energy storage, poses new challenges and opportunities to grid management and operation. Rapid growth of distribution automation as well as equipment monitoring technologies in the distribution grids further offer new opportunities for distribution asset management. The idea of aggregated DERs is proposed as a remedy to streamline management and operation of advanced distribution grids, as discussed under three subjects in this dissertation. The first subject matter focuses on …


Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi Jan 2020

Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi

Electronic Theses and Dissertations

An increased usage in IoT devices across the globe has posed a threat to the power grid. When an attacker has access to multiple IoT devices within the same geographical location, they can possibly disrupt the power grid by regulating a botnet of high-wattage IoT devices. Based on the time and situation of the attack, an adversary needs access to a fixed number of IoT devices to synchronously switch on/off all of them, resulting in an imbalance between the supply and demand. When the frequency of the power generators drops below a threshold value, it can lead to the generators …


Nyku: A Social Robot For Children With Autism Spectrum Disorders, Dan Stephan Stoianovici Jan 2020

Nyku: A Social Robot For Children With Autism Spectrum Disorders, Dan Stephan Stoianovici

Electronic Theses and Dissertations

The continued growth of Autism Spectrum Disorders (ASD) around the world has spurred a growth in new therapeutic methods to increase the positive outcomes of an ASD diagnosis. It has been agreed that the early detection and intervention of ASD disorders leads to greatly increased positive outcomes for individuals living with the disorders. Among these new therapeutic methods, Robot-Assisted Therapy (RAT) has become a hot area of study. Recent works have shown that high functioning ASD children have an affinity for interacting with robots versus humans. It is proposed that this is due to a less complex set of communication …


Power System Frequency Control And Stability Analysis With Increasing Renewable Energy Penetration Level, Weihang Yan Jan 2020

Power System Frequency Control And Stability Analysis With Increasing Renewable Energy Penetration Level, Weihang Yan

Electronic Theses and Dissertations

With the ever-increasing penetration level of renewable energy generation units and the replacement of traditional synchronous generators, the issues associated with the deteriorated performance of power system frequency regulation and potential grid frequency instability become more significant. In this dissertation, the inertial control algorithms are investigated and analyzed for power electronics converter in a renewable energy generation unit. The concept and design of Virtual Synchronous Generator are comprehensively discussed, such that the small-signal stability and frequency stability of power systems with high renewable energy penetration level can be enhanced. Moreover, both nonlinear dynamic model and small-signal linearization of Virtual Synchronous …


Ultrasonic-Based Condition Assessment Of Wooden Utility Poles, Yishi Lee Jan 2020

Ultrasonic-Based Condition Assessment Of Wooden Utility Poles, Yishi Lee

Electronic Theses and Dissertations

More than 300 million utility poles shoulder the utility grid in the United States. However, the ineffectiveness of the current inspection process causes roughly a third of utility poles removed from the service deemed suitable for reuse. Due to the utterly essential role of the power infrastructure, budget shrinkage, and the structural degradation of the modern distribution grid, this Ph.D. dissertation addresses the challenges by proposing a physics-based signal analysis method with a jointly developed ultrasonic UB1000 system c to enhance the objectivity in ultrasonic-based nondestructive evaluation (NDE). The proposed methodology has been deployed commercially in the field and featured …


Impact Of Grid-Following And Grid-Forming Ders On Resilient Operation Of Holonic Grid, Ali M. Alsenan Jan 2020

Impact Of Grid-Following And Grid-Forming Ders On Resilient Operation Of Holonic Grid, Ali M. Alsenan

Electronic Theses and Dissertations

This thesis investigates how different distributed energy resources (DERs) impact the resilience operation of a holonic grid. The holonic grid consists of two or more connected microgrids and /or provisional microgrids (PMGs). The type of the DER, i.e., grid-forming or grid-following, affects the operations of the holonic grid, particularly during the islanded mode. To study this emerging and timely topic, a resilience-oriented holonic grid optimal operation model is proposed. This model carefully formulates the operations of both grid-forming and grid-following DERs. A variable value of lost load (VoLL) is further employed in the proposed model to help quantify and monetize …


Control Strategy For A Small-Scale Microgrid Based On Battery Energy Storage System-Virtual Synchronous Generator (Bess-Vsg), Wei Gao Jan 2019

Control Strategy For A Small-Scale Microgrid Based On Battery Energy Storage System-Virtual Synchronous Generator (Bess-Vsg), Wei Gao

Electronic Theses and Dissertations

As one of widely deployed renewable energy resources, PV power is playing a very important role in microgrids today. It has advantages such as making the best of natural solar energy and being friendly to our environment. In this thesis, solar PV based microgrid is studied using modeling and simulation. Microgrid can run in either grid-connected-mode or islanded-mode. However, there are also some disadvantages for solar power. For solar panel, its output is influenced by weather conditions such as illumination intensity and temperature. In addition, during the control process of grid-connected mode, it is hard to guarantee its output power …


Power System Resilience Enhancement Using Artificial Intelligence, Rozhin Eskandarpour Jan 2019

Power System Resilience Enhancement Using Artificial Intelligence, Rozhin Eskandarpour

Electronic Theses and Dissertations

Extreme weather events and natural disasters are the major cause of power outages in the United States. An accurate forecast of component outages and the resultant load curtailment in response to extreme events is an essential task in pre- and post-event planning, recovery and hardening of power systems. Power system resilience improvement is investigated in this work from component outage prediction to identifying the potential power outages in the system to estimating probable load curtailment due to these outages and offering methods for grid hardening. Initially, two machine learning based prediction methods are proposed to determine the potential outage of …


Paving The Way For Multidisciplinary Smart Campus Infrastructure: Leveraging Du's Unique Campus For The Advancement Of Smart Campus Culture, Camerron T. Mismash Jan 2019

Paving The Way For Multidisciplinary Smart Campus Infrastructure: Leveraging Du's Unique Campus For The Advancement Of Smart Campus Culture, Camerron T. Mismash

Electronic Theses and Dissertations

Institutions are embracing smart technologies to reap their benefits while simultaneously innovating new uses. From localized renewable energy generation to health monitoring and everything in between, academic campuses globally are paving the way for smart technology application. Eight primary categories have been identified in which institutions are applying smart technologies. Energy development is on the forefront of these smart initiatives. The University of Denver has begun its Smart Campus Initiative by implementing a revolving fund to invest in campus improvements related to the offset of carbon. By comparing how institutions are investing in smart campus initiatives and analyzing costs associated …


Safe And Efficient Intelligent Intersection Control Of Autonomous Vehicles, Qiang Lu Jan 2019

Safe And Efficient Intelligent Intersection Control Of Autonomous Vehicles, Qiang Lu

Electronic Theses and Dissertations

In this dissertation, we address a problem of safe and efficient intersection crossing traffic management of autonomous and connected ground traffic. Toward this objective, we propose several algorithms to handle different traffic environments. First, an algorithm that is called the Discrete-time occupancies trajectory (DTOT) based Intersection traffic Coordination Algorithm (DICA) is proposed. All vehicles in the system are Connected and Autonomous Vehicles (CAVs) and capable of wireless Vehicle-to-Intersection communication. The main advantage of DICA is that it enables us to utilize the intersection space more efficiently resulting in less delay for vehicles to cross the intersection. In the proposed framework, …


Radar Detection, Tracking And Identification For Uav Sense And Avoid Applications, Erik George Moore Jan 2019

Radar Detection, Tracking And Identification For Uav Sense And Avoid Applications, Erik George Moore

Electronic Theses and Dissertations

Advances in Unmanned Aerial Vehicle (UAV) technology have enabled wider access for the general public leading to more stringent flight regulations, such as the "line of sight" restriction, for hobbyists and commercial applications. Improving sensor technology for Sense And Avoid (SAA) systems is currently a major research area in the unmanned vehicle community. This thesis overviews efforts made to advance intelligent algorithms used to detect, track, and identify commercial UAV targets by enabling rapid prototyping of novel radar techniques such as micro-Doppler radar target identification or cognitive radar. To enable empirical radar signal processing evaluations, an S-Band and X-Band frequency …


Nonlinear Controller Design For Uavs With Time-Varying Aerodynamic Uncertainties, Michail G. Michailidis Jan 2019

Nonlinear Controller Design For Uavs With Time-Varying Aerodynamic Uncertainties, Michail G. Michailidis

Electronic Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) are here and they are here to stay. Unmanned Aviation has expanded significantly in recent years and research and development in the field of navigation and control have advanced beyond expectations. UAVs are currently being used for defense programs around the world but the range of applications is expected to grow in the near future, with civilian applications such as environmental and aerial monitoring, aerial surveillance and homeland security being some representative examples. Conventional and commercially available small-scale UAVs have limited utilization and applicability to executing specific short-duration missions because of limitations in size, payload, power …


Design And Analysis Of A Non-Isolated High Gain Step-Up Cuk Converter, Yasser Almalaq Jan 2019

Design And Analysis Of A Non-Isolated High Gain Step-Up Cuk Converter, Yasser Almalaq

Electronic Theses and Dissertations

Renewable energy sources, such as solar energy, are desired for both economic and ecological issues. These renewable energy sources are plentiful in nature and have a terrific capability for power generation. The only drawback of solar energy, which is one of the best forms of energy sources, is that the output has a low voltage and needs to be stepped up in order to be inserted into the DC grid or an inverter for AC applications. To overcome this drawback, a high gain DC-DC power converter is required in this kind of system. These power converters are needed for a …


Increasing Distribution Grid Hosting Capacity Through Wire And Non-Wire Solutions, Abdulrahman N. Almazroui Jan 2019

Increasing Distribution Grid Hosting Capacity Through Wire And Non-Wire Solutions, Abdulrahman N. Almazroui

Electronic Theses and Dissertations

Increased deployment of distributed generation (DG) can adversely impact the operational performance of distribution networks. This increment can potentially change network power flow and result in several operational issues such as reduced power quality, overvoltage, and ineffective protection. In order to quantify the degradation bounds of distribution operation due to increasing DG integration, the concept of hosting capacity is introduced. The aim of this thesis is to increase the DG hosting capacity in distribution network by proposing several wire and non-wire solutions. To this end, these solutions include network reconfiguration, reactive power control, and energy storage system deployment. The network …


Small-Scale Microgrid Energy Market Based On Pilt-Dao, Tianlu Gao Jan 2019

Small-Scale Microgrid Energy Market Based On Pilt-Dao, Tianlu Gao

Electronic Theses and Dissertations

With the installed capacities of Distributed Generations (DGs) dramatically increasing in power systems from Distributed Energy Resources (DERs) such as hydropower, wind, solar, geothermal and biomass, the operation methods of DERs tradings or transactions become more and more complicated. However, the energy market of DERs in Microgrids (MGs) is still under devolvement due to low security and transparency at present. Therefore, a small-scale microgrid energy market is proposed in this study based on Decentralized Autonomous Organization of Parallel, Integrity, Longevity, and Transparency (PILT-DAO) of the features of the blockchain. The microgrid owners can complete the transaction in the PILT-DAO market. …


Capturing Transmission And Distribution Connected Wind Energy Variability, Abdulaziz Alanazi Jan 2019

Capturing Transmission And Distribution Connected Wind Energy Variability, Abdulaziz Alanazi

Electronic Theses and Dissertations

Although renewable energy provides a viable solution to address ongoing challenges of the economy and the environment in modern power systems, the variable generation of this technology results in major technical challenges for system operators. This issue is becoming more severe as the penetration of renewable generation is increasing. This dissertation addresses the variability challenge of renewable energy resources in transmission and distribution levels of modern power systems.

For transmission level, this dissertation focuses on wind generation fluctuation. Three methods of reducing wind generation fluctuation are investigated from an economic perspective, including (a) dumping the wind generation, (b) using battery …


Solar Forecasting And Integration In Power Systems, Mohana Alanazi Jan 2019

Solar Forecasting And Integration In Power Systems, Mohana Alanazi

Electronic Theses and Dissertations

Renewable energy resources are becoming critical players in the electricity generation sector, primarily due to viability in combating global warming, effectiveness in reducing pollution caused by fossil fuel based generation, and diversifying energy mix to ensure energy security and sustainability. Solar energy is one of the most common types of renewable energy that has grown rapidly over the past decade and is anticipated to grow even faster in the future. Power supply from renewable resources is forecasted to surpass other types of generation in a foreseeable future. Numerous factors, including but not limited to the dropping cost of solar technology, …


Highly Efficient Gan-Based Single-Phase Transformer-Less Pv Grid-Tied Inverter, Khaled Alatawi Jan 2019

Highly Efficient Gan-Based Single-Phase Transformer-Less Pv Grid-Tied Inverter, Khaled Alatawi

Electronic Theses and Dissertations

Growing energy demand and environmental concerns have led to an increased interest in renewable energy resources to provide a sustainable and low carbon emission energy supply. Among these renewable energy resources, photovoltaic (PV) systems have been the focus of many scientific researchers. The most vital component of a PV system that needs to be improved is the power converter. Grid-tied transformer-less inverters have gained a lot of interest in recent years because of their higher efficiency, reduced volume and lower cost compared to traditional line transformer inverters.

This dissertation discusses single-phase transformer-less inverter challenges and provides solutions that could lead …


Proactive Monitoring, Anomaly Detection, And Forecasting Of Solar Photovoltaic Systems Using Artificial Neural Networks, Ahmad Almadhor Jan 2019

Proactive Monitoring, Anomaly Detection, And Forecasting Of Solar Photovoltaic Systems Using Artificial Neural Networks, Ahmad Almadhor

Electronic Theses and Dissertations

The world of energy sustainability landscape is witnessing high proliferation of smartgrids and microgrids, it has become significant to use intelligent tools to design, operate and maintain such crucial systems in our lives. Solar energy is an intermittent source and purely Photovoltaic (PV) based, or PV and storage based smartgrids require characterization and modelling of PV resources for an effective planning and effective operations. This dissertation familiarizes briefly the existing tools for design, monitoring, forecasting and operation of a solar system in smart electric grids infrastructure and proposes a unique application-based infrastructure to monitor, operate, forecast and troubleshoot a working …


Modeling And Control Of The Ugv Argo J5 With A Custom-Built Landing Platform, Mohammed Aldaoseri Alghanim Jan 2019

Modeling And Control Of The Ugv Argo J5 With A Custom-Built Landing Platform, Mohammed Aldaoseri Alghanim

Electronic Theses and Dissertations

This thesis aims to develop a detailed dynamic model and implement several navigation controllers for path tracking and dynamic self-leveling of the Argo J5 Unmanned Ground Vehicle (UGV) with a custom-built landing platform. The overall model is derived by combining the Argo J5 driveline system with the wheelsterrain interaction (using terramechanics theory and mobile robot kinetics), while the landing platform model follows the Euler-Lagrange formulation. Different controllers are, then, derived, implemented to demonstrate: i.) self-leveling accuracy of the landing platform, ii.) trajectory tracking capabilities of the Argo J5 when moving in uneven terrains. The novelty of the Argo J5 model …


Distribution Level Building Load Prediction Using Deep Learning, Abdulaziz S. Almalaq Jan 2019

Distribution Level Building Load Prediction Using Deep Learning, Abdulaziz S. Almalaq

Electronic Theses and Dissertations

Load prediction in distribution grids is an important means to improve energy supply scheduling, reduce the production cost, and support emission reduction. Determining accurate load predictions has become more crucial than ever as electrical load patterns are becoming increasingly complicated due to the versatility of the load profiles, the heterogeneity of individual load consumptions, and the variability of consumer-owned energy resources. However, despite the increase of smart grids technologies and energy conservation research, many challenges remain for accurate load prediction using existing methods. This dissertation investigates how to improve the accuracy of load predictions at the distribution level using artificial …


Supervised Machine Learning Techniques For Short-Term Load Forecasting, Harish Amarasundar Jan 2019

Supervised Machine Learning Techniques For Short-Term Load Forecasting, Harish Amarasundar

Electronic Theses and Dissertations

Electric Load Forecasting is essential for the utility companies for energy management based on the demand. Machine Learning Algorithms has been in the forefront for prediction algorithms. This Thesis is mainly aimed to provide utility companies with a better insight about the wide range of Techniques available to forecast the load demands based on different scenarios. Supervised Machine Learning Algorithms were used to come up with the best possible solution for Short-Term Electric Load forecasting. The input Data set has the hourly load values, Weather data set and other details of a Day. The models were evaluated using MAPE and …


A Study On Distributed Generation With A Focus On Solar Power, Shravan Kumar Tomar Jan 2019

A Study On Distributed Generation With A Focus On Solar Power, Shravan Kumar Tomar

Electronic Theses and Dissertations

Centralized generation is when electric power is produced in a large scale of tens of MWs and is located away from the end user. This kind of production is connected to a series of high-voltage transmission lines. Electricity is then delivered to the end user through a network of distribution grids. Centralized generation tend to have multiple end user with multiple user profiles.

Distributed Generation is when is produced in a small scale and is located at the site of or very close to the end user. There are many ways distributed generation can be achieved, Solar power being the …


Design And Evaluation Of High Efficiency Power Converters Using Wide-Bandgap Devices For Pv Systems, Fahad Almasoudi Aug 2018

Design And Evaluation Of High Efficiency Power Converters Using Wide-Bandgap Devices For Pv Systems, Fahad Almasoudi

Electronic Theses and Dissertations

The shortage of fossil resources and the need for power generation options that produce little or no environmental pollution drives and motivates the research on renewable energy resources. Power electronics play an important role in maximizing the utilization of energy generation from renewable energy resources. One major renewable energy source is photovoltaics (PV), which comprises half of all recently installed renewable power generation in the world. For a grid-connected system, two power stages are needed to utilize the power generated from the PV source. In the first stage, a DCDC converter is used to extract the maximum power from the …


Optimal Planning Of Microgrid-Integrated Battery Energy Storage, Ibrahim S. Alsaidan Jan 2018

Optimal Planning Of Microgrid-Integrated Battery Energy Storage, Ibrahim S. Alsaidan

Electronic Theses and Dissertations

Battery energy storage (BES) is a core component in reliable, resilient, and cost-effective operation of microgrids. When appropriately sized, BES can provide the microgrid with both economic and technical benefits. Besides the BES size, it is found that there are mainly three planning parameters that impact the BES performance, including the BES integration configuration, technology, and depth of discharge.

In this dissertation, the impact of each one of these parameters on the microgrid-integrated BES planning problem is investigated. Three microgrid-integrated BES planning models are developed to individually find the optimal values for the aforementioned parameters. These three microgrid-integrated BES planning …


Study Of Optical Ofdm System For Wireless Lan Applications, Salih Mohamed S. Kenshil Jan 2018

Study Of Optical Ofdm System For Wireless Lan Applications, Salih Mohamed S. Kenshil

Electronic Theses and Dissertations

The advantages of optical fiber make it possible to extend the data rate transmission and propagation distance. Orthogonal frequency division multiplexing (OFDM) as a multicarrier technique (MC) is used in hybrid optical-wireless system designs because it has the best spectral efficiency to radio frequency (RF) interference and lower multipath distortion. In this dissertation, a study and evaluation of optical OFDM based wireless local area network (W-LAN) systems are presented. The baseband of the OFDM signal is fully transmitted and up-converted to a radio frequency signal. Also, to reduce system costs, simple base stations (BSs) are interconnected to a central office …


Robust Distributed Stabilization Of Interconnected Multiagent Systems, Vahid Rezaei Jan 2018

Robust Distributed Stabilization Of Interconnected Multiagent Systems, Vahid Rezaei

Electronic Theses and Dissertations

Many large-scale systems can be modeled as groups of individual dynamics, e.g., multi-vehicle systems, as well as interconnected multiagent systems, power systems and biological networks as a few examples. Due to the high-dimension and complexity in configuration of these infrastructures, only a few internal variables of each agent might be measurable and the exact knowledge of the model might be unavailable for the control design purpose. The collective objectives may range from consensus to decoupling, stabilization, reference tracking, and global performance guarantees. Depending on the objectives, the designer may choose agent-level low-dimension or multiagent system-level high-dimension approaches to develop distributed …


Hosting Capacity Optimization In Modern Distribution Grids, Mansoor T. Alturki Jan 2018

Hosting Capacity Optimization In Modern Distribution Grids, Mansoor T. Alturki

Electronic Theses and Dissertations

The availability of distributed renewable energy resources and the anticipated increase in new types of loads are changing the way electricity is being produced and supplied to consumers. This shift is moving away from a network delivering power solely from centralized power plants towards a decentralized network which supplements its power production by incorporating local distributed generators (DGs). However, the increased integration of DGs into existing distribution networks is impacting their behavior in terms of voltage profile, reliability, and power quality. To determine the maximum amount of DG that distribution grids can accommodate the concept of hosting capacity is introduced. …


Optimal Operation Of Integrated Microgrids, Abdullah Albaker Jan 2018

Optimal Operation Of Integrated Microgrids, Abdullah Albaker

Electronic Theses and Dissertations

Microgrids' deployments are increasing and projected to increase even more in future due to the significant advantages that are provided by this technology for end-use customers. However, microgrids can be connected to each other to create integrated microgrids system, which can further promote the anticipated and desired benefits. An integrated operation of microgrids can potentially improve the local power system reliability and resilience, increase the individual microgrids' economic benefits, and promote further utilization of renewable energy resources. Integrating microgrids, to achieve a microgrid network or cluster, is expected be an essential application towards smarter power grids and a key operational …


Automated Cfd Optimization To Maximize Wind Farms Performance And Land Use, Rafael Valotta Rodrigues Jan 2018

Automated Cfd Optimization To Maximize Wind Farms Performance And Land Use, Rafael Valotta Rodrigues

Electronic Theses and Dissertations

In this research, a computational system was designed to analyze and optimize the layout of wind farms under variable operational conditions. At first, a wind turbine computational fluid dynamic (CFD) model was developed covering the near wake. The near wake flow field was validated against near wake velocity data from the MEXICO experiment. The CFD simulation demonstrated that the tip speed ratio and the pitch angle greatly influence the near wake behavior, affecting the velocity deficit and the turbulence intensity profile in this region. The CFD model was extended to cover the far wake, aiming to become a computational tool …