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Articles 511 - 540 of 579
Full-Text Articles in Electrical and Electronics
Solar Powered Backpack, Saagar Sabharwal, Tom Poonsopin
Solar Powered Backpack, Saagar Sabharwal, Tom Poonsopin
Electrical Engineering
One popular motto in electrical engineering today is “going green.” This project will convert the sun’s energy into reusable energy. The purpose of this senior project is to develop a solar powered backpack that can charge certain portable USB devices for students. Many students walk around campus with an iPod or cell phone, which has surely died or ran low on batteries at least once when needed most. This backpack will allow students to charge their devices “on the go.” When students walk or bike around campus, the solar panels attached to the backpack will allow recharging of their portable …
Design And Simulation Of V2g Bidirectional Inverter And Dc-Dc Converter, Allan Agatep, Mason Ung
Design And Simulation Of V2g Bidirectional Inverter And Dc-Dc Converter, Allan Agatep, Mason Ung
Electrical Engineering
As plug-in hybrid electric vehicles (PHEV) become more popular, the utility companies are forced to feed the grid more electricity. However, these PHEVs are capable of providing power to the grid when they are parked serving as ancillary systems for grid regulation (V2G). Using a system based on photovoltaic (PV) technology, a design for a bidirectional inverter with LCL filter, and a bidirectional dc-dc with a constant current controller, was constructed using LTspice. Various papers were researched and analyzed to determine applicable designs for components. Simulations show the designs are capable of bidirectional power transfer. ETAP simulations show that delivering …
Project 308: Augmented Reality Mario Kart, Joseph Abad, David Allender, Joryl Calizo, Ryan Gaspar, Gavin Lee
Project 308: Augmented Reality Mario Kart, Joseph Abad, David Allender, Joryl Calizo, Ryan Gaspar, Gavin Lee
Computer Engineering
Mario Kart is a popular go-kart racing game developed by Nintendo. The premise of the game is simple: drive a go-kart along a racetrack and reach the finish line before the other players. What makes this game unique, however, is the inclusion of weapons, traps, and other projectiles that a player can use to gain an advantage in the race. We have taken on the challenge of not only recreating this amazing game, but using the art of Augmented Reality to fully immerse the player in the full experience. Rather than play the game on a television screen with a …
Current Tracking Power Supply For Sensor Calibration, Joshua Brookley
Current Tracking Power Supply For Sensor Calibration, Joshua Brookley
Electrical Engineering
This report highlights the steps taken to design and develop a constant 5V power supply capable of tracking load current. The background of its previous design, its necessary specifications and steps taken to achieve specifications are highlighted throughout the report. The report also contains conclusions and final recommendations for the design chosen, including its strengths and drawbacks.
Imu Integration To The Cal Poly Spacecraft Attitude Dynamics Simulator Power System, Wayland Chan
Imu Integration To The Cal Poly Spacecraft Attitude Dynamics Simulator Power System, Wayland Chan
Electrical Engineering
The Cal Poly Spacecraft Attitude Dynamics Simulator mimics the rotation dynamics of a spacecraft in orbit and acts as a test bed for spacecraft attitude control system development and demonstration. Prior to this project, the simulator measured its attitude dynamics from a total of seven sensors mounted on to the platform, including three micro-electromechanical system (MEMs) gyroscopes, and four motor encoders. This project entails the installation of an LN-200 high performance gyroscope, which will provide a greater measure of accuracy. The goal of this project is to design a power circuit that will integrate the LN-200 inertial measurement unit onto …
Wireless Sensor Network For Energy And Environmental Monitoring: Helping Old Buildings Go Green, Jacob Power
Wireless Sensor Network For Energy And Environmental Monitoring: Helping Old Buildings Go Green, Jacob Power
Electrical Engineering
Today, the rising cost of energy and social trend of “going green” has put increasing pressure on commercial property owners to improve the efficiency of their investments. There is good reason for this, too. In the State of California, office buildings represent the single largest user of energy in the commercial sector. This project consisted of the design, implementation, construction, testing, and deployment of a wireless sensor network for energy and environmental monitoring in retrofit commercial office installations. The analyzed data generated by this system can be used by building management and owners to identify areas of inefficiency within the …
Photovoltaic Emulator Adaptable To Irradiance, Temperature And Panel Specific I-V Curves, Joseph Gamos Durago
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 …
Energy Harvesting From Elliptical Machines Using Four-Switch Buck-Boost Topology, Alvin Jay Hilario
Energy Harvesting From Elliptical Machines Using Four-Switch Buck-Boost Topology, Alvin Jay Hilario
Master's Theses
This thesis presents the topic of using the Four-Switch Buck-Boost topology as a DC-DC converter for the Energy Harvesting from Elliptical Machines Project. The project works toward providing a modular synchronous power generation system. Due to the dynamic and sporadic output voltage and power characteristics of the Precor elliptical machine, the system requires a DC-DC converter as a voltage preregulator. The inherent wide input range, high efficiency, and low parts cost of this converter well suit the application. This paper further discusses other topologies and their shortcomings, as well as characterizes the Precor elliptical machine and Enphase Microinverter for interfacing. …
Elliptical Machine Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Greg Hollister
Elliptical Machine Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Greg Hollister
Electrical Engineering
Designing a DC/DC Converter for the Cal Poly Energy Harvesting from Exercise Machines project requires special attention to the unique operating characteristics of the source and the load. An elliptical machine powered by a person exercising comprises the source, while an AC Inverter makes up the load. This project attempts to integrate the two devices with a custom DC/DC Converter in order to ultimately deliver power back into the power grid.
Electric Motor & Power Source Selection For Small Aircraft Propulsion, Jeremy Fehrenbacher, David L. Stanley, Mary E. Johnson Dr., Jeffrey Honchell
Electric Motor & Power Source Selection For Small Aircraft Propulsion, Jeremy Fehrenbacher, David L. Stanley, Mary E. Johnson Dr., Jeffrey Honchell
Purdue Polytechnic Directed Projects
The research conducted in this project is on electrical propulsion in aviation. A Cessna 172K aircraft with a Lycoming O-320-E2D piston engine serves as a baseline measurement. Investigation of the components required for electrical flight is performed, and components are selected based on market availability and operational performance criteria.
This research focuses on electrical propulsion in the aviation industry, and is tailored to aircraft within the General Aviation sector leading to the following research question: Can current electric motor and battery technologies conceptually support flight operations for a Cessna 172K in terms of aircraft performance criteria?
The results explore the …
Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton
Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton
Master's Theses
This thesis investigates a relatively new method for harvesting wind energy by using flexible piezoelectric polymers with additional sails to increase their ability to harvest wind energy. This paper also introduces a new topology deemed the “stacked buck” that allows for multiple inputs to a system with a single output. Derivations and analysis detail the workings of the “stacked buck” with a laboratory test to show a working model. This paper also reports another experiment done in a wind tunnel to analyze the capability of the piezoelectric polymers as sources to the “stacked buck” topology with measurements of the power …
"Buried-Anode" Technology Leads To Advanced Lithium Batteries, National Renewable Energy Laboratory
"Buried-Anode" Technology Leads To Advanced Lithium Batteries, National Renewable Energy Laboratory
Publications (E)
A technology developed at the National Renewable Energy Laboratory has sparked a start-up company that has attracted funding from the Advanced Projects Research Agency-Energy (ARPA-E). Planar Energy, Inc. has licensed NREL's "buried-anode" technology and put it to work in solid-state lithium batteries. The company claims its large-format batteries can achieve triple the performance of today's lithium-ion batteries at half the cost, and if so, they could provide a significant boost to the emerging market for electric and plug-in hybrid vehicles.
Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Articles
In this paper a technical review of parallel operation of power electronics inverters for load sharing conditions in distributed generation (DG) network is presented. Emphasis is given to parallel operation of Active Power Filters (APFs) as they are widely used to mitigate load current disturbances into DG networks. Discussions on recent advances in control strategies as applied to APFs are presented.
Wireless Energy Transfer, Ryan Sasur
Wireless Energy Transfer, Ryan Sasur
Electrical Engineering
Phones are now an integral component in the daily lives of people. Smartphones give access to movies, internet, and even books. This versatility and increased use can also lead to a shorter battery life. A phone with video viewing capabilities will be a heavy load on the unit’s battery. With phones utilizing 3G and 4G technology, even heavier demands are placed on the battery. As technology improves even further to provide for a larger entertainment experience on the phone, this could also lead to further battery degradation if the current battery situation isn’t addressed. To have a fully operational phone …
Hydro-Electric Generation System For The Dc House Project, Dennis Kwan, Mitchell Krug
Hydro-Electric Generation System For The Dc House Project, Dennis Kwan, Mitchell Krug
Electrical Engineering
This paper focuses on the design, integration, and construction of a system that harnesses energy from flowing water. The system will be used in conjunction with the DC House Project. The proposed system employs a DC generator and DC-DC Boost-converter to provide electricity to the DC House at approximately 200-300W. Results of the testing and measurement show that the goal of the system is feasible, but currently limited. The generator could not output the specified power. Details of the design, along with ideas for further improvement, are presented in this report.
Energy Efficient Led Displays, John Mani Kumar Jupalli
Energy Efficient Led Displays, John Mani Kumar Jupalli
UNLV Theses, Dissertations, Professional Papers, and Capstones
In this research work, an innovative pixel architecture RGBW, consisting of red (R), green (G), blue (B), and white (W) LEDs, is designed and implemented for color generation. Energy consumption of new pixel architecture consisting of RGBW LEDs is compared to standard architecture consisting of RGB LEDs. Human perception experiments are conducted to study the differences in perception between the two architectures when the same colors are generated using RGBW vs. RGB. Measurements of power for a 32inch x 16inch LED display has proved up to 18% power savings for low saturated colors, up to 8% for high saturated colors …
Energy Storage And Management For A Small Series Plug-In Hybrid Electric Vehicle, Liqin Ni
Energy Storage And Management For A Small Series Plug-In Hybrid Electric Vehicle, Liqin Ni
Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research
Plug-in hybrid electric vehicles (PHEVs) are gaining increasing interest for both residential and commercial transportation applications. In PHEV design, energy storage system (EES) is a critical component which will impact the overall design efficiency, performance, cost and etc. This dissertation aims to design an advanced energy storage system for a small plug-in hybrid electric vehicle, whose performance will approach very closely to the optimal possible, in terms of energy efficiency and acceleration, for passenger road vehicles application. Moreover, practical automotive requirements are considered during ESS design, such as cost, life time, safety and volume.
This dissertation utilizes ultracapacitors in conjunction …
Economic Optimization Of Offshore Wind Farms Using The Geometric Algorithm, Mahidhar Nandigam
Economic Optimization Of Offshore Wind Farms Using The Geometric Algorithm, Mahidhar Nandigam
Electrical & Computer Engineering Theses & Dissertations
The research project related to this thesis focuses on the optimization of electrical systems for offshore wind farms for a given capacity. The optimal design and planning is a critical issue for developing cost effectively Offshore Wind Farms in energy systems. The Geometric Optimization Algorithms approach has been adopted to develop an optimization program, where the main components of the electrical system of an offshore wind farm and key technical specifications are used as parameters to be optimized for a minimum cost with necessary constraints. The effectiveness of the optimization program can be evaluated with real-time comparison between offshore wind …
The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle
The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle
Conference papers
The paper describes a method to control the rotor-side and grid side converters in a DFIG when subjected to the effects of network voltage unbalance conditions. Multi Frequency Resonant Controllers are incorporated into the grid side and rotor side converters to assist in the control functions. The Resonant Controllers are tuned to twice the network frequency to assist in the control of power and torque pulsations and to three times the network frequency to assist in the control of the generated third harmonic currents. A DFIG model is implemented in Matlab/Simulink and simulations show the reduction in power and torque …
The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle
The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle
Conference papers
The paper describes a method to control the rotor-side and grid side converters in a DFIG when subjected to the effects of network voltage unbalance conditions. Multi Frequency Resonant Controllers are incorporated into the grid side and rotor side converters to assist in the control functions. The Resonant Controllers are tuned to twice the network frequency to assist in the control of power and torque pulsations and to three times the network frequency to assist in the control of the generated third harmonic currents. A DFIG model is implemented in Matlab/Simulink and simulations show the reduction in power and torque …
Wavelet Based Islanding Detection Of Dc-Ac Inverter Interfaced Dg Systems, Mohamed Moin Hanif, Malabika Basu, Kevin Gaughan
Wavelet Based Islanding Detection Of Dc-Ac Inverter Interfaced Dg Systems, Mohamed Moin Hanif, Malabika Basu, Kevin Gaughan
Conference papers
The increased penetration of distributed generation (DG) often connected to grid through dc-ac interface has made islanding detection an important and challenging issue to power engineers. Several methods based on passive and active detection scheme have been proposed in the literature. While passive schemes have a large non detection zone (NDZ), concern has been raised on active method due to its degrading power quality effect. This paper proposes a wavelet based passive islanding detection scheme with almost zero NDZ for dc-ac inverter interfaced grid connected DGs. The key idea is to utilize the spectral changes in the higher frequency components …
Enhanced Cal Poly Super System Simulink Model, Matthew Ogden Mcfarland
Enhanced Cal Poly Super System Simulink Model, Matthew Ogden Mcfarland
Master's Theses
The Cal Poly Sustainable Power for Electrical Resources (SuPER) project is a solar power DC distribution system designed to autonomously manage and supply the energy needs of a single family off-the-grid home. The following thesis describes the improvement and re-design of a MATLAB Simulink model for the Cal Poly SuPER system. This model includes a photovoltaic (PV) array, a lead-acid gel battery with temperature effects, a wind turbine model, a re-designed DC-DC converter, a DC microgrid, and multiple loads. This thesis will also include several control algorithms such as a temperature controlled thermoelectric (T.E.) cooler, intelligent load switching, and an …
Asynchronous Mips Processors: Educational Simulations, Robert L. Webb
Asynchronous Mips Processors: Educational Simulations, Robert L. Webb
Master's Theses
The system clock has been omnipresent in most mainstream chip designs. While simplifying many design problems the clock has caused the problems of clock skew, high power consumption, electromagnetic interference, and worst-case performance. In recent years, as the timing constraints of synchronous designs have been squeezed ever tighter, the efficiencies of asynchronous designs have become more attractive. By removing the clock, these issues can be mitigated. How- ever, asynchronous designs are generally more complex and difficult to debug. In this paper I discuss the advantages of asynchronous processors and the specifics of some asynchronous designs, outline the roadblocks to asynchronous …
Validated Real-Time Energy Models For Small-Scale Grid-Connected Pv-Systems, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon
Validated Real-Time Energy Models For Small-Scale Grid-Connected Pv-Systems, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon
Articles
This paper presents validated real-time energy models for small-scale grid-connected PV-systems suitable for domestic application. The models were used to predict real-time AC power output from a PV system in Dublin, Ireland using 30-min intervals of measured performance data between April 2009 and March 2010. Statistical analysis of the predicted results and measured data highlight possible sources of errors and the limitations and/or adequacy of existing models, to describe the temperature and efficiency of PV-cells and consequently, the accuracy of power prediction models. PV-system AC output power predictions using empirical models for PV-cell temperature and efficiency prediction showed lower percentage …
The Applications And Limitations Of Printable Batteries, Matthew Delmanowski
The Applications And Limitations Of Printable Batteries, Matthew Delmanowski
Graphic Communication
This study focuses on the potential applications for printed batteries and how they could affect the printing industry. It also analyzes the main problems associated with manufacturing this technology and what needs to be done to overcome these issues. To find the answers to these questions, two methods of research were used. The first was through the elite and specialized interviewing of Dr. Scott Williams of Rochester Institute of Technology and Professor Nancy Cullins from Cal Poly. The second form of research was a common, yet useful, method called secondary research. This entailed looking at recent written research papers about …
Pulse Density Modulated Soft Switching Cycloconverter, Jesse Timothy Adamson
Pulse Density Modulated Soft Switching Cycloconverter, Jesse Timothy Adamson
Master's Theses
Single stage cycloconverters generally incorporate hard switching at turn on and soft switching at turn off. This hard switching at turn on combined with the slow switching speeds of thyristors (the switch of choice for standard cycloconverters) limits their use to lower frequency applications.
This thesis explores the analysis and design of a pulse density modulated (PDM), soft switching cycloconverter. Unlike standard cycloconverters, the controller in this converter does not adjust thyristor firing angles. It lets only complete half cycles of the input waveform through to the output. This allows and requires a much greater frequency step down from the …
Electric Bicycle System, Robert Cong, Rodney Martinez, Mark Casilang, Peter Vong
Electric Bicycle System, Robert Cong, Rodney Martinez, Mark Casilang, Peter Vong
Electrical Engineering
The Electric Bicycle System is a systems project that incorporates three different ways of charging a lithium-ion battery: the 120VAC wall outlet, regenerative braking, and solar power; which is used to power an electric hub motor running a bicycle. The purpose of the project is to show that it is possible and relatively simple, to build an electric bicycle by oneself. This project can be broken down into five separate categories: the lithium-ion battery, the DC-DC boost converter, the solar panel, the motor, and the motor controller. Each of these will be built upon and improved further by future students, …
Magnetic Design Web Application, Michael Brim
Magnetic Design Web Application, Michael Brim
Electrical Engineering
The automated Magnetic Design Web Application, available at http://www.magneticdesign.org, generates the full design process of a power transformer, gapped inductor and toroidal inductor given design specifications provided by the user. Calculations are accomplished using Area Product, Ap, or Core Geometry, Kg, procedures. All design processes mirror the format used in Dr. Taufik’s Introduction to Magnetic Design lecture-notes. An administrative backend is provided where instructors can add or modify core design values to expand the array of materials used. The project aims to aid student understanding of magnetic design and course concepts while allowing instructors to broaden the scope of material …
Electric Field Computation Of Wet Insulating Surfaces, Bhargavi Sarang
Electric Field Computation Of Wet Insulating Surfaces, Bhargavi Sarang
Electrical & Computer Engineering Theses & Dissertations
High voltage outdoor insulators form the backbone of modem power systems and therefore play a pivotal role in reliable supply of power. The presence of water droplets/films due to rain, fog, etc. enhances the electric field intensity and leads to electrical breakdown subsequently affecting the longevity of the insulator. The magnitude of surface E-fields necessary for initiation of electrical breakdown is a function of water repellent characteristic of an insulator called hydrophobicity. Thus, knowledge of field distribution around water droplets/films at various hydrophobic levels is significant in designing a better insulating material.
The current research analyzed electric field distributions on …
Power Quality In Grid Connected Renewable Energy Systems: Role Of Custom Power Devices, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Power Quality In Grid Connected Renewable Energy Systems: Role Of Custom Power Devices, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Conference papers
This paper deals with the technical review of power quality problems associated with the renewable based distributed generation systems and how the custom power devices like STATCOM, DVR and UPQC play important role in power quality improvement. IEEE and IEC standard for the grid connected renewable energy systems are one of the critical point of interest for the selection of custom power devices. Special attention has been given on the compensation of reactive power, harmonic current and voltage fluctuation during the interconnected as well as islanding mode of operation. As the solar and wind are the most abundant resources therefore …