Engineering Commons^™

Distributed Coordination And Control Of Renewable Energy Sources In Microgrids, Javad Khazaei Khazaei

USF Tampa Graduate Theses and Dissertations

Microgrid is an emerging technology in the eld of electrical engineering which employs the concept of Distributed Energy Resources (DERs) in order to generate electricity in a small sized power system. The main objectives of this dissertation are to: 1- design a new control for lower level control of DERs in microgrids, 2- implement distributed upper level control for DERs in microgrids and 3- apply analytical approaches in order to analyze DERs in microgrids. The control in each DER can be divided into two main categories: lower and upper level. Lower level control is the main objective of control in …

Fabrication Of Cu2Znsnse4 Thin-Film Solar Cells By A Two-Stage Process, Yejiao Wang

USF Tampa Graduate Theses and Dissertations

Copper zinc tin selenide (Cu₂ZnSnSe₄ or CZTSe) is a quaternary compound semiconductor material that has attained more and more attention for thin film photovoltaic applications. CZTSe is only comprised of abundant and non-toxic elements. People have concerns about availability and cost of indium from CIGS and tellurium from CdTe, also about cadmium’s toxicity. These concerns have promoted CZTSe as an alternative thin film solar cell material. The major issues about CZTSe absorber fabrication are: tin loss during selenization process and existence of secondary phases. Recent improvements of CZTSe absorber have increased the efficiency of CZTSe thin film …

Synthesis And Characterization Of Kesterite Cu2znsns4 (Czts) Thin Films For Solar Cell Application, Mohamed M.A. Abusnina

Electronic Theses and Dissertations

The quaternary compound Cu₂ZnSnS₄ (CZTS) gained considerable attention in the last decade due to its potential as an active-layer semiconductor for low-cost thin-film solar cells. The material is composed of nontoxic and Earth-abundant constituents, has optical properties suitable for photovoltaic application, and can be synthesized using a wide variety of methods.

Polycrystalline CZTS was grown in this work using vacuum-based deposition to first deposit metal films (precursors) of Cu, Zn, and Sn. In a subsequent step, the precursors underwent an annealing treatment in sulfur vapor environment (sulfurization) to form CZTS. Using sputtering, a physical vapor deposition (PVD) …

Photovoltaics: An Investigation Into The Origins Of Efficiency On All Scales, Jeremy Alexander Bannister

Senior Projects Spring 2016

This project is comprised of a set of parallel investigations, which share the common mo- tivation of increasing the efficiency of photovoltaics. First, the reader is introduced to core concepts of photovoltaic energy conversion via a semi-classical description of the phys- ical system. Second, a key player in photovoltaic efficiency calculations, the exciton, is discussed in greater quantum mechanical detail. The reader will be taken through a nu- merical derivation of the low-energy exciton states in various geometries, including a line segment, a circle and a sphere. These numerical calculations are done using Mathematica, a computer program which, due to …

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …

Control System Design, Analysis, And Simulation Of A Photovoltaic Inverter For Unbalanced Load Compensation In A Microgrid, Elizabeth K. Tomaszewski

Electronic Thesis and Dissertation Repository

This thesis presents a control scheme for a single-stage three-phase Photovoltaic (PV) converter with negative sequence load current compensation.

In this thesis a dual virtual impedance active damping technique for an LCL filter is proposed to address the issue of LCL filter resonance. Both inverter-side current and the capacitor current are used in the feedback loop. Using both signals provides higher DC rejection than using capacitor current alone. The proposed active damping scheme results in a faster transient response and higher damping ratio than can be obtained using inverter-side current alone. The feedback gains can be calculated to achieve a …

A Computational Study Of A Photovoltaic Compound Parabolic Concentrator, William M. Vance

Browse all Theses and Dissertations

Routines have been written and added to the Wright State developed solar system simulation program called Solar_PVHFC to model incident solar radiation for a compound parabolic concentrator (CPC) that uses solar panels (photovoltaic panels) to produce electrical energy. Solar_PVHFC is a program that models a solar energy system composed of solar panels to produce electricity from the sun, hydrogen storage tanks to chemically store the energy produced by the solar panels, and fuel cells to convert between electrical and chemical energy when required. Solar_PVHFC features several adjustable parameters to model a solar panel, hydrogen storage, and fuel cell system. Now …

Optimal Techno-Economic Sizing Of Wind/Solar/Battery Hybrid Microgrid System Using The Forever Power Method, Sami Hamed Alalwani

Masters Theses

"Advancement in power electronics, energy storage, control, and renewable energy sources has led to the use of integrated renewable energy sources in islanded microgrids (MG). Also, the uses of integrated renewable energy sources have become more technically applicable, more economically feasible, and more environmentally friendly than conventional sources. As a result, electrification of rural villages using renewable energy technologies has started to become widely adopted around the world. Since generating power from renewable energy sources is highly intermittent and difficult to predict, the use of proper energy storage technology is important to eliminate mismatches between the load demand and generation. …

Life Cycle Assessment Projection Of Photovoltaic Cells: A Case Study On Energy Demand Of Quantum Wire Based Photovoltaic Technology Research, Shilpi Mukherjee

Graduate Theses and Dissertations

With increasing clean-energy demand, photovoltaic (PV) technologies have gained attention as potential long-term alternative to fossil fuel energy. However, PV research and manufacture still utilize fossil fuel-powered grid electricity. With continuous enhancement of solar conversion efficiency, it is imperative to assess whether overall life cycle efficiency is also being enhanced. Many new-material PV technologies are still in their research phase, and life cycle analyses of these technologies have not yet been performed. For best results, grid dependency must be minimized for PV research, and this can be accomplished by an analytical instrument called Life Cycle Assessment (LCA).

LCA is the …

Cascaded Inverters For Grid-Connected Photovoltaic Systems, Bailu Xiao

Doctoral Dissertations

With the extraordinary market growth in grid-connected PV systems, there is increasing interests in grid-connected PV inverters. Focus has been placed on cheap, high-efficiency, and innovative inverter solutions, leading to a high diversity within the inverters and new system configurations. This dissertation chooses cascaded multilevel inverter topologies for grid-connected PV systems to reduce the cost and improve the efficiency.

First, a single-phase cascaded H-bridge multilevel PV inverter is discussed. To maximize the solar energy extraction of each PV string, an individual maximum power point tracking (MPPT) control scheme is applied, which allows independent control of each dc-link voltage. A generalized …

Control Of Grid-Connected Photovoltaic Systems Using Fractional Order Operators, Hadi Malek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work presents a new peak seeking strategy for maximum power point operation using fractional order operators in the three-phase grid-connected photovoltaic systems. Moreover, fractional order controllers have been implemented in the voltage and current control loops. The simulation results and theoretical analysis indicate that the proposed fractional order control strategy improves the efficiency of the system by reducing the total harmonic distortion of the injected current to the grid and increases the robustness of the system against uncertainties. Additionally, the proposed maximum power point tracking algorithms provide more robustness and faster convergence speed under environmental variations than other maximum …

Optical Properties Of Solar Cells Based On Zinc(Hydr)Oxide And Its Composite With Graphite Oxide Sensitized By Quantum Dots, S. M. Zakirul Islam

Dissertations, Theses, and Capstone Projects

This thesis research focuses on developing a hybrid form of solar cell based on zinc(hydr)oxide and its composites with graphite oxide, TiO2, quantum dot, electrolyte and . This work expands upon the Gratzel solar cell with a dye in TiO2.

Due to various structural and optical characteristics, zinc(hydr)oxide (Zn(OH)2) and its porous composites with 2% and 5% graphite oxide(GO) can be used for various applications including the manufacture of various , protective elements in electric and electronic appliances, as gas-sensors, catalysts, in cosmetics a UV light absorber, and solar cells.

In this research, both TiO2 and zinc(hydr)oxide (refer as Zn(OH)2 …

The Effect Of Annealing On Amorphous Silicon Based Solar Photovoltaic Thermal System (Pv/T) And Appropriate Global Dispatch Strategies, Joseph Rozario

Dissertations, Master's Theses and Master's Reports - Open

Previous work has shown that high-temperature short-term spike thermal annealing of hydrogenated amorphous silicon (a-Si:H) photovoltaic thermal (PVT) systems results in higher electrical energy output. The relationship between temperature and performance of a-Si:H PVT is not simple as high temperatures during thermal annealing improves the immediate electrical performance following an anneal, but during the anneal it creates a marked drop in electrical performance. In addition, the power generation of a-Si:H PVT depends on both the environmental conditions and the Staebler-Wronski Effect kinetics. In order to improve the performance of a-Si:H PVT systems further, this paper reports on the effect of …

Maximum Power Point Tracking Device For A Photovoltaic Panel, Betsy Schwartz

Honors Theses

The operating characteristics of a photovoltaic (PV) solar panel are dependent upon the lighting and temperature conditions, as well as the characteristics of the energy storage device and/or loads that it feeds. PV panels normally operate at a fixed voltage and current for a given load and sunlight condition. The operating conditions will not necessarily produce the maximum possible power output of a solar panel for the set conditions. The efficiency of power delivery from a PV panel can be greatly increased by a Maximum Power Point Tracker (MPPT). An algorithm can be designed to shift the operating value to …

Off Grid Solar Powered Street Light, Justin Fang, Billy Pham

Electrical Engineering

Street lights are fixtures found in every city and serve the important purpose of illuminating the streets and keeping the roads safe for pedestrians and drivers. Current street lights are powered by the grid, power which is paid for by the taxpayers and could have been used to power homes instead. With this project, our goal is to design and implement an electric power system that collects and stores solar energy, and delivers power to an LED smart street light. The resulting system would reduce street light energy costs by 100% since they would not draw any power from the …

Impact Of Photovoltaic System Penetration On The Operation Of Voltage Regulator Equipment, Abesh Sorab Mubaraki

Master's Theses

The growing popularity of photovoltaic (PV) generation systems leads to an increase in the number of residential and commercial grid-tied PV systems that interconnect to the distribution circuit. This affects the characteristics of the distribution circuit; for example, the assumption that the voltage profile of a radial line decreases down-stream becomes invalid because of the addition of the PV system on the line. This poses new challenges when setting the parameters of voltage regulating devices. Add to that the fact that PV systems are intermittent, especially on cloudy days, which make the line even more difficult to regulate, and the …

Time Domain Simulation Of Novel Photovoltaic Materials, Haejun Chung

Open Access Theses

Thin-film silicon-based solar cells have operated far from the Shockley- Queisser limit in all experiments to date. Novel light-trapping structures, however, may help address this limitation. Finite-difference time domain simulation methods offer the potential to accurately determine the light-trapping potential of arbitrary dielectric structures, but suffer from materials modeling problems. In this thesis, existing dispersion models for novel photovoltaic materials will be reviewed, and a novel dispersion model, known as the quadratic complex rational function (QCRF), will be proposed. It has the advantage of accurately fitting experimental semiconductor dielectric values over a wide bandwidth in a numerically stable fashion. Applying …

Copper Indium Diselenide Nanowire Arrays In Alumina Membranes Deposited On Molybdenum And Other Back Contact Substrates, Bhavananda R. Nadimpally

Theses and Dissertations--Electrical and Computer Engineering

Heterojunctions of CuInSe₂ (CIS) nanowires with cadmium sulfide (CdS) were fabricated demonstrating for the first time, vertically aligned nanowires of CIS in the conventional Mo/CIS/CdS stack. These devices were studied for their material and electrical characteristics to provide a better understanding of the transport phenomena governing the operation of heterojunctions involving CIS nanowires. Removal of several key bottlenecks was crucial in achieving this. For example, it was found that to fabricate alumina membranes on molybdenum substrates, a thin interlayer of tungsten had to be inserted. A qualitative model was proposed to explain the difficulty in fabricating anodized aluminum oxide …

Residential Grid-Tied With Battery Backup Photovoltaic System, Thomas Stobuagh

Electrical Engineering

When power outages occur, many homes are left without power for some time as they are dependent on the power grid. This project aims to design a residential grid tied battery backup photovoltaic system that will provide up to 7.2kW in an area that gets 5.36-5.49 kWh/m2/day [1] to support a home with an average daily usage of 28.4 kWh/day. To effectively use this system the house remains connected to the electric utility at all times, so any power needed above what the solar system can produce is simply drawn from the utility. It includes battery backup or uninterruptible power …

Multipolymer Interactions In Bulk Heterojunction Photovoltaic Devices, Grant Olson

Physics

Multipolymer photovoltaics, single layer devices made up of multiple photoactive polymers, can create organic photovoltaics (OPVs) with a wider spectral response than single polymer systems without the difficult fabrication of a tandem. Our group has successfully created multipolymer solar devices with 2% power conversion efficiency. We have analyzed the optical and electrical properties of these devices, and found that it may be possible for polymers to assist each other with charge extraction, though combining polymers disrupts single polymer crystallinity.

Dynamic Modelling Of Single Phase Grid Connected Photovoltaic System, Gopi Krishna Ari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Grid-connected photovoltaic (PV) power systems have been sustaining an exponential growth rate during the past decade. This steep growth is driven by a growing concern about climate change, the adoption of an aggressive regional renewable portfolio standard, rebates and tax incentives, and reduction in PV system cost. One of the main technical barriers that can ultimately limit further PV penetration is the fast variations in the PV system's output power induced by cloud transients. Such events are known to cause voltage fluctuations which may lead to excessive operations of voltage regulation equipment and light flickering.

Solar irradiance variability, which can …

Reactive Power Considerations In Reliability Analysis Of Solar Photovoltaic Systems, Dattatray N. Gaikwad

LSU Master's Theses

Reliability is one of the key aspects of power system operation and therefore reliability analysis techniques are well developed. However reliability analysis conventionally takes into account active power and limited attention has been given to reactive power. Reactive power is very essential in maintaining voltage stability of power systems. The voltage constraint at network can restricts active power delivery to the loads and could result in forced load curtailment. This research investigates the effect of reactive power shortage on reliability of power systems with significant penetration of PV cells. The reactive power issues become more significant in distributed generation using …

Benefits Of Near-Term Cloud Location Forecasting For Large Solar Pv, Timothy Robert Rudd

Master's Theses

As the ‘green’ energy movement continues to gain momentum, photovoltaic generation is becoming an increasingly popular source for new power generation. The primary focus of this paper is to demonstrate the benefits of close-to real-time cloud sensing for Photovoltaic generation. In order to benefit from this close-to real-time data, a source of cloud cover information is necessary. This paper looks into the potential of point insolation sensors to determine overhead cloud coverage. A look into design considerations and economic challenges of implementing such a monitoring system is included. The benefits of cloud location sensing are examined using computer simulations to …

Solar Instrumentation Lab, Rene Canedo Iii, Rong Gui Chen

Electrical Engineering

This project is a mobile platform that will allow experiments on different solar panels to be done easily while keeping the cost of the lab to a minimum. California Polytechnic State University’s motto is ‘learn by doing’ and this lab structure will allow students to get practical experience with photovoltaic cells and the instruments that are required to take measurements. The solar instrumentation lab is a potential hardware lab for the electrical engineering department’s Sustainable Electric Energy Conversion class EE 420 and Solar-Photovoltaic Systems Design EE 520. This group took the current solar structure as a base for the lab’s …

Photovoltaic Emulator Adaptable To Irradiance, Temperature And Panel Specific I-V Curves, Joseph Gamos Durago

Master's Theses

This thesis analyzes the design and performance of a photovoltaic (PV) emulator. With increasing interest in renewable energies, large amounts of money and effort are being put into research and development for photovoltaic systems. The larger interest in PV systems has increased demand for appropriate equipment with which to test PV systems.

A photovoltaic emulator is a power supply with similar current and voltage characteristics as a PV panel. This work uses an existing power supply which is manipulated via Labview to emulate a photovoltaic panel. The emulator calculates a current-voltage (I-V) curve based on the user specified parameters of …

Free Space Optical Communications With High Intensity Laser Power Beaming, Daniel Edward Raible

ETD Archive

This research demonstrates the feasibility of utilizing high intensity laser power beaming (HILPB) systems as a conduit for robust free-space optical communications over large distances and in challenging atmospheric conditions. The uniqueness of vertical multi-junction (VMJ) photovoltaic cells used in HILPB systems in their ability to receive and to convert at high efficiency, very high intensity laser light of over 200 W/cm2, presents a unique opportunity for the development of the robust free space optical communication system by modulating information signals onto the transmitted high intensity photonic energy. Experiments were conducted to investigate and validate several optical communications concepts. A …

Effects Of Cloud-Induced Photovoltaic Power Transients On Power System Protection, Joel A. Nelson

Master's Theses

As the world strives towards finding alternative sources of power generation, photovoltaic generation has become an increasingly prevalent alternative energy source on power systems world-wide. This paper studies the effects that incorporating photovoltaic generation has on the existing power systems and their power system protection schemes. Along with the addition of this emerging alternative energy source comes the volatility of PV power generation as cloud-cover produces erratic variations in solar irradiance and PV power production. Such variations in PV power may lead to unfavorable operating conditions and power system failures. The issues addressed in this paper include a study of …

Designing A Photovoltaic System Hybrid For A Health Clinic In Camilo Ortega, Nicaragua, Jeremy Holliman

Electrical Engineering

As developing nations continue to foster the development of their technologies and economies, industrialized nations have taken an active approach in providing green and sustainable alternatives for them to consider. Non-profit organizations like Engineers Without Borders holds sustainable international development as paramount to all international projects that their student and professional chapters undertake. The Cal Poly Engineers Without Borders student chapter has implemented a variety of projects from slow sand filters to compressed earth blocks, and the Nicaragua team is in the process of designing a health clinic for the Camilo Ortega community. In order to power the health clinic, …

Green Organic Solar Cells From A Water Soluble Polymer And Nancrystalline Tio2, Qiquan Qiao

Theses and Dissertations

The cost of the present generation of inorganic silicon solar cells is very high and further breakthroughs in cost and efficiency using traditional materials are becoming less and less likely after over 50 years of development. Next generation organic solar cells offer a solution to the limitations of silicon through the vision of low-cost, liquid-based, large area fabrication technology based on polymer and nanomaterials at room temperature. However, most polymers used in solar cells are dissolved in organic solvents such as xylene, toluene, chloroform, and chlorobenzene. Such solvents are harmful to people and environments, leading to higher costs due to …

Preparation And Characterization Of Cigss Solar Cells And Pv Module Data Analysis, Jyoti Shirolikar

Electronic Theses and Dissertations

In this thesis, multiple activities have been carried out in order to improve the process of CIGSS solar cell fabrication on a 4" x 4" substrate. The process of CIGSS solar cell fabrication at FSEC's PV Materials Lab involves a series of steps that were all carried out manually in the past. A LABVIEW program has been written to carry out automated sputter deposition of Mo back contact, CuGa, In metallic precursors on a soda lime glass substrate using a stepper motor control for better uniformity. Further, selenization/ sulfurization of these precursors was carried out using rapid thermal processing (RTP). …