Engineering Commons^™

Fault Discrimination Algorithm For Busbar Differential Protection Relaying Using Partial Operating Current Characteristics, Monir Hossain

University of New Orleans Theses and Dissertations

Differential protection is the unit protection system which is applied to protect a particular unit of power systems. Unit is known as zone in protection terminology which is equivalent to simple electrical node. In recent time, low impedance current differential protection schemes based on percentage restrained characteristics are widely used in power systems to protect busbar systems. The main application issue of these schemes is mis-operation due to current transformer (CT) saturation during close-in external faults. Researchers have suggested various solution of this problem; however, individually they are not sufficient to puzzle out all mis-operational scenarios. This thesis presents a …

Optimal Dg Placement: A Multimethod Analysis, Saiful A. Ratul

University of New Orleans Theses and Dissertations

With Power System being restructured in the vision of Smart Grid, it is important now more than ever to find suitable locations to place Distributed Generators (DG). Distributed generators, which may be renewable, are not limited to specific locations as in the case of conventional generators. Several papers have been published that make suggestions on where the optimal location of DG should be in a system. Objectives ranging from loss minimization to total cost minimization have been the factor for such studies. In this study, a new method is introduced that hopes to improve a current system in three ways …

Studies Of Uncertainties In Smart Grid: Wind Power Generation And Wide-Area Communication, Can Huang

Doctoral Dissertations

This research work investigates the uncertainties in Smart Grid, with special focus on the uncertain wind power generation in wind energy conversion systems (WECSs) and the uncertain wide-area communication in wide-area measurement systems (WAMSs).

For the uncertain wind power generation in WECSs, a new wind speed modeling method and an improved WECS control method are proposed, respectively. The modeling method considers the spatial and temporal distributions of wind speed disturbances and deploys a box uncertain set in wind speed models, which is more realistic for practicing engineers. The control method takes maximum power point tracking, wind speed forecasting, and wind …

Design, Control And Protection Of Modular Multilevel Converter (Mmc)-Based Multi-Terminal Hvdc System, Yalong Li

Doctoral Dissertations

Even though today’s transmission grids are predominantly based on the high voltage alternating current (HVAC) scheme, interests on high voltage direct current (HVDC) are growing rapidly during the past decade, due to the increased penetration of remote renewable energy. Voltage source converter (VSC) type is preferred over the traditional line-commutated converter (LCC) for this application, due to the advantages like smaller station footprint and no need for strong interfacing ac grid. As the state-of-the-art VSC topology, modular multilevel converter (MMC) is mostly considered. Most renewable energy sources, such as wind and solar, is usually sparsely located. Multi-terminal HVDC (MTDC) provides …

A Study On Wide-Area Measurement-Based Approaches For Power System Voltage Stability, Haoyu Yuan

Doctoral Dissertations

With the development of wide-area monitoring system (WAMS) enabled by the synchrophasor technology, measurement-based approaches for power system voltage stability and control have been widely discussed in recent years. Based on high-frequency synchronized measurement signals collected from phasor measurement units (PMUs), these approaches have great potentials to significantly improve the situational awareness and to effectively guide the controls of interconnected modern power systems.

If compared with conventional model-based voltage stability assessment (VSA) and control methods, the measurement-based methods are relatively new. Although their simplicity and independence of system models make them suitable for online deployment, the applications of these measurement-based …

Selective Resistive Sintering: A Novel Additive Manufacturing Process, Austin Bryan Van Horn

Graduate Theses and Dissertations

Selective laser sintering (SLS) is one of the most popular 3D printing methods that uses a laser to pattern energy and selectively sinter powder particles to build 3D geometries. However, this printing method is plagued by slow printing speeds, high power consumption, difficulty to scale, and high overhead expense. In this research, a new 3D printing method is proposed to overcome these limitations of SLS. Instead of using a laser to pattern energy, this new method, termed selective resistive sintering (SRS), uses an array of microheaters to pattern heat for selectively sintering materials. Using microheaters offers significant power savings, significantly …

Development, Characterization, & Implementation Of Phase-Change Material Cold Plates For Hybrid-Electric Vehicle Battery Systems, Kevin Cwiok

Doctoral Dissertations and Master's Theses

Due to the regulations on internal combustion engine vehicles, there is a large demand of hybrid and electric vehicles with large battery packs as Energy Storage Systems (ESS) capable of long ranges and decreased emissions. These battery packs output large heat loads during charge-depletion mode and currently require active cooling to keep the batteries within operating conditions. The current systems relied onto achieve this are the air and liquid cooled thermal managements systems. A recent alternative approach to current cooling for ESS thermal management is the use of phase-change materials (PCMs). PCMs regulate the temperature of the ESS by leveraging …

Optimal Sensing And Transmission In Energy Harvesting Sensor Networks, Xianwen Wu

Graduate Theses and Dissertations

Sensor networks equipped with energy harvesting (EH) devices have attracted great attentions recently. Compared with conventional sensor networks powered by batteries, the energy harvesting abilities of the sensor nodes make sustainable and environment-friendly sensor networks possible. However, the random, scarce and non-uniform energy supply features also necessitate a completely different approach to energy management.

A typical EH wireless sensor node consists of an EH module that converts ambient energy to electrical energy, which is stored in a rechargeable battery, and will be used to power the sensing and transmission operations of the sensor. Therefore, both sensing and transmission are subject …

Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang

Electronic Theses and Dissertations

This dissertation studies two separate topics in wireless communication systems. One topic focuses on the Single Carrier Frequency Domain Equalization (SC-FDE), which is a promising technique to mitigate the multipath effect in the broadband wireless communication. Another topic targets on the energy efficiency optimization in a multiple input multiple output (MIMO) cognitive radio network. For SC-FDE, the conventional linear receivers suffer from the noise amplification in deep fading channel. To overcome this, a fractional spaced frequency domain (FSFD) receiver based on frequency domain oversampling (FDO) is proposed for SC-FDE to improve the performance of the linear receiver under deep fading …

Photovoltaic Cooking In The Developing World, Tyler Watkins, Christopher O'Day, Omar Arriaga

Mechanical Engineering

The challenge of clean cooking is faced by hundreds of millions of people worldwide. We present a cooking technology consisting of a solar panel directly connected to an electric heater in a well-insulated chamber. Assuming continued decrease in solar panel prices, we anticipate that in a few decades Solar Electric Cooking technologies will be the most common cooking technology for the poor. Appropriate use of insulation reduces the power demand making low-power Insulated Solar Electric Cooking systems already cost competitive.

Electric Smart Load Meter, Johnny Tran

Electrical Engineering

This project details the design of an electric meter that reads the signals of any device plugged into an outlet and displays cost readings that may potentially reduce power consumption. The sensor monitors whether a plugged in device continuously consumes power after completely charging up. For a charging device, the current remains constant until the device reaches 100% charge. Once the device becomes fully charged, the current discontinues for proper power usage. A unique aspect of the meter is that it displays cost per hour, day, and year. Displaying the cost per unit of time creates awareness for customers, potentially …

Designing A Power Distribution System For The Arce 257 Revit Structural Model, Reid Wilhelm

Electrical Engineering

The construction industry needs engineers. Mechanical, electrical, and plumbing engineers, better known as MEPs, comprise a large number of employees who design and assist in the building of commercial structures. In particular, electrical engineers design power distribution systems for these buildings, including the power, lighting, low voltage, and fire protection subsystems.

Here at Cal Poly, architectural engineers enrolled in ARCE 257 create authentic structural plans for a fictitious two-story structure. This senior project transforms these structural plans into an architectural model and creates a power distribution system for the entire building. This is done through a building information modeling (BIM) …

Power Distribution:Protection Analysis, Avneet S. Samra

Electrical Engineering

The objective of this project is to build a radial distribution system that operates on a lower voltage. The system consists of a transmission line protected by a SEL-351 Relay, a three- phase transformer protected by a SEL-587 Relay, and a three-phase induction motor protected by a Cooper Form 6 Controller. The SEL-351, SEL-587, and the Cooper Form 6 Controller are microprocessor-based relays that are used to provide protection under faulted conditions. When a fault is detected in the system, the closest upstream relay sends a trip signal to its assigned local breaker. The SEL-351 provides overcurrent protection for the …

Optimized Sizing And Placing Of Distributed Energy Resources (Ders) In An Island Microgrid Using Der-Cam, Bhuwan B. Bastola

Electrical and Computer Engineering ETDs

The electric grid at La Gomera, an island in the Canary archipelago, has been the subject of interest in optimized integration of Distributed Energy Resources (DERs) primarily because of high distribution losses and concerns about complying with emission regulations. Consequently, the utility that operates the island power system wishes to mitigate the problem with installation of renewable and distributed energy sources like PV and battery, which is the focus of this research.

Specifically, the focus of this thesis is to use Distributed Energy Resource - Customer Adoption Model (DER-CAM) to optimize the installation of PV and battery in terms of …

Plasticized Polymer Coatings For Sh-Saw Sensors For High Sensitivity And Long-Term Monitoring Of Btex Analytes In Liquid Phase, Pintu Adhikari

Master's Theses (2009 -)

BTEX compounds (benzene, toluene, ethylbenzene, and xylene) are constituents of crude oil and hazardous to human health. Among them, benzene has the lowest maximum contaminant level for drinking water because of its carcinogenicity. Spills or leakage from underground storage tanks or hazardous waste sites can contaminate nearby groundwater with these volatile organic compounds. Therefore, it is very important to detect the presence of BTEX contamination as early as possible in order to start the remediation process and maintain a healthy environment. To develop an in-situ continuous monitoring sensor system, shear horizontal surface acoustic wave (SH-SAW) sensor devices are being investigated …

Configuring The Urban Smart Grid: Transitions, Experimentation, And Governance, Anthony Michael Levenda

Dissertations and Theses

In the face of challenges of energy security, decarbonization, resilience, and the replacement of aging infrastructure systems, federal, state, and local actors are facilitating the development of smart electricity networks to transition towards a more sustainable electricity system. In the United States, development of "smart grids" is being pursued as a national policy mandate and goal, promising that the deployment of smart grid technologies -- referring in general to digital information and communication technologies that sense, monitor, control and manage the electric grid -- will make electricity systems more environmentally sustainable and reliable, and at the same time, provide opportunities …

Numerical And Experimental Study Of The Trichel Pulses In Needle-Plane Geometry, Peyman Dordizadeh Basirabad

Electronic Thesis and Dissertation Repository

One of the unique aspects of the negative corona discharges in the air is the regular train of pulses that form the discharge current, called Trichel pulses. These pulses are the result of the combination of several phenomena such as the avalanche ionization of the neutral molecules by the impact of the energized electrons, formation of the cloud of positive ions close to the cathode, and formation of the cloud of negative ions at a farther distance from the corona electrode compared to their positive counterparts. In this thesis, the results of a detailed numerical investigation of the formation of …

Analysis And Mitigation Of Temporary Over-Voltage (Tov) Phenomenon In Unintentionally Islanded Grid-Connected Photovoltaic (Pv) Inverters, Md Maruful Islam

Electronic Thesis and Dissertation Repository

Grid-connected photovoltaic (PV) solar systems, like other inverter-based distributed generators, can cause temporary over-voltages (TOVs), especially subsequent to faults and unintentional islanding incidents, and can damage equipment and customers within the host distribution network. Thus, this thesis aims to study the phenomenon and propose corrective measures for it. Thus, the thesis first presents detailed models for a conventional single-stage PV system and a modified single-stage PV system. The conventional system uses a Δ/YG isolation transformer, whereas the modified system, proposed in the literature, assumes a Y/YG isolation transformer that is effectively grounded by an additional half-bridge leg energized by the …

Identification Of Critical Locations And Reduced Model State Estimation For Power System Analysis, Amamihe Onwuachumba

Electronic Theses and Dissertations

In order to reduce the carbon footprint and the cost of electric energy, the owners of electric power utilities today are faced with the task of reducing the use of expensive and carbon intensive fossil fuels and significantly increasing the amount of energy from renewable sources in their grids while meeting an increase in electricity demand. To deal with increase in demand, electric utilities operate very close to their maximum capacities and this sometimes results in violating security limits. Therefore, the integration of intermittent renewable energy into the utility grids poses serious concerns that must be addressed to ensure grid …

Optimal Scheduling Of Energy Storage For Energy Shifting And Ancillary Services To The Grid, Hadi Khani

Electronic Thesis and Dissertation Repository

This thesis is mainly focused on developing optimization-based models for scheduling of energy storage units. At first, a real-time optimal scheduling algorithm is developed seeking to maximize the storage revenue by exploiting arbitrage opportunities available due to the inter-temporal variation of electricity prices. The electricity price modulation is proposed as an approach to competitively offer incentive by the utility regulator to storage to fill the gap between current and a stable rate of return. Subsequently, the application of large-scale storage for congestion relief in transmission systems as an ancillary service to the grid is investigated. An algorithm is proposed for …

Wide-Area Measurement-Based Applications For Power System Monitoring And Dynamic Modeling, Jidong Chai

Doctoral Dissertations

Due to the increasingly complex behavior exhibited by large-scale power systems with more uncertain renewables introduced to the grid, wide-area measurement system (WAMS) has been utilized to complement the traditional supervisory control and data acquisition (SCADA) system to improve operators’ situational awareness. By providing wide-area GPS-time-synchronized measurements of grid status at high time-resolution, it is able to reveal power system dynamics which cannot be captured before and has become an essential tool to deal with current and future power grid challenges. According to the time requirements of different power system applications, the applications can be roughly divided into online applications …

Dynamic Modeling And Renewable Integration Studies On The U.S. Power Grids, Gefei Kou

Doctoral Dissertations

Wind and solar generation have gained a significant momentum in the last five years in the United States. According to the American Wind Energy Association, the installed wind power capacity has tripled from 25,410 MW in early 2009 to 74,472 MW as of the end of 2015. Meanwhile, solar photovoltaic (PV) is reported that its capacity has skyrocketed from 298 MW in 2009 to 7,260 MW in 2015 by the Solar Energy Industries Association. Despite the fact that wind and solar only make up 4.4% and 0.4% , respectively, of total electricity generation in 2014, the nation is right on …

Data Analytics And Application Developments Based On Synchrophasor Measurements, Jiahui Guo

Doctoral Dissertations

Frequency Monitoring Network (FNET) is an Internet‐based, wide‐area phasor measurement system that collects power system data using Frequency Disturbance Recorders (FDRs) that are installed at the distribution level. These synchrophasor measurements enable the monitoring of bulk power systems, and provides wide‐area situational awareness and disturbance analysis for understanding power system disturbances and system operations. Various data analytics and applications are built based on these valuable measurements.

Real-time situational awareness tools are of critical importance to power system operators. Knowledge of the scope and extent of facilities impacted, as well as the duration of their dependence on backup power, enables emergency …

Bi-Level Optimization Considering Uncertainties Of Wind Power And Demand Response, Xin Fang

Doctoral Dissertations

Recently, world-wide power systems have been undergone a paradigm change with increasing penetration of renewable energy. The renewable energy is clean with low operation cost while subject to significant variability and uncertainty. Therefore, integration of renewables presents various challenges in power systems. Meanwhile, to offset the uncertainty from renewables, demand response (DR) has gained considerable research interests because of DR’s flexibility to mitigate the uncertainty from renewables. In this dissertation, various power system problems using bi-level optimization are investigated considering the uncertainties from wind power and demand response.

In power system planning, reactive power planning (RPP) under high-penetration wind power …

Review And Characterization Of Gallium Nitride Power Devices, Edward Andrew Jones

Masters Theses

Gallium Nitride (GaN) power devices are an emerging technology that have only recently become available commercially. This new technology enables the design of converters at higher frequencies and efficiencies than those achievable with conventional Si devices. This thesis reviews the characteristics and commercial status of both vertical and lateral GaN power devices from the user perspective, providing the background necessary to understand the significance of these recent developments. Additionally, the challenges encountered in GaN-based converter design are considered, such as the consequences of faster switching on gate driver design and board layout. Other issues include the unique reverse conduction behavior, …

Real-Time Voltage Stability Monitoring And Control For Load Areas: A Hybrid Approach, Fengkai Hu

Doctoral Dissertations

This dissertation proposes a hybrid approach for real-time monitoring and controlling voltage stability of a load area fed by N tie lines. This hybrid approach integrates both simulation-based and measurement-based approaches for voltage stability assessment (VSA).

First, for measurement-based VSA (MBVSA), a new method is proposed for monitoring and control of load areas, which adopts an N+1 buses equivalent system so as to model and monitor individual tie lines of a load area compared to a traditional MBVSA method adopting a Thevenin equivalent. For each tie line, the new method solves the power transfer limit against voltage instability analytically …

The Influence Of The Electric Supply Industry On Economic Growth In Less Developed Countries, Edward Richard Bee

Dissertations

This study measures the impact that electrical outages have on manufacturing production in 135 less developed countries using stochastic frontier analysis and data from World Bank’s Investment Climate surveys. Outages of electricity, for firms with and without backup power sources, are the most frequently cited constraint on manufacturing growth in these surveys.

Outages are shown to reduce output below the production frontier by almost five percent in Africa and by a lower percentage in South Asia, Southeast Asia and the Middle East and North Africa. Production response to outages is quadratic in form. Outages also increase labor cost, reduce exports …

Determining The Power And Energy Capacity Of A Battery Energy Storage System Utilizing A Smoothing Feeder Profile To Accommodate High Photovoltaic Penetration On A Distribution Feeder, Osama Mohammed Abbas Aly Mansour

Dissertations and Theses

Electricity is a perishable commodity; once it is generated it needs to be consumed or stored. Electric energy storage provides both power and energy capacity. Power capacity applications reduce the need for generation, while energy capacity allows for energy consumption to be decoupled from generation. Previous research was done to develop an algorithm for determining the power (MW) and energy (MWh) capacities of a battery energy storage system (BESS) to mitigate the adverse impacts of high levels of photovoltaic (PV) generation. The algorithm used a flat feeder profile, and its performance was demonstrated on the equinoxes and solstices.

Managing feeder …

Wake Character In The Wind Turbine Array: (Dis-)Organization, Spatial And Dynamic Evolution And Low-Dimensional Modeling, Nicholas Michael Hamilton

Dissertations and Theses

To maximize the effectiveness of the rapidly increasing capacity of installed wind energy resources, new models must be developed that are capable of more nuanced control of each wind turbine so that each device is more responsive to inflow events. Models used to plan wind turbine arrays and control behavior of devices within the farm currently make questionable estimates of the incoming atmospheric flow and update turbine configurations infrequently. As a result, wind turbines often operate at diminished capacities, especially in arrays where wind turbine wakes interact and inflow conditions are far from ideal. New turbine control and wake prediction …

Simulation, Measurement, And Emulation Of Photovoltaic Modules Using High Frequency And High Power Density Power Electronic Circuits, Yunas Erkaya

Electrical & Computer Engineering Theses & Dissertations

The number of solar photovoltaic (PV) installations is growing exponentially, and to improve the energy yield and the efficiency of PV systems, it is necessary to have correct methods for simulation, measurement, and emulation. PV systems can be simulated using PV models for different configurations and technologies of PV modules. Additionally, different environmental conditions of solar irradiance, temperature, and partial shading can be incorporated in the model to accurately simulate PV systems for any given condition.

The electrical measurement of PV systems both prior to and after making electrical connections is important for attaining high efficiency and reliability. Measuring PV …