Engineering Commons^™

Broadband High Efficiency Fractal-Like And Diverse Geometry Silicon Nanowire Arrays For Photovoltaic Applications, Omar Hassan Al-Zoubi

Graduate Theses and Dissertations

Solar energy has many advantages over conventional sources of energy. It is abundant, clean and sustainable. One way to convert solar energy directly into electrical energy is by using the photovoltaic solar cells (PVSC). Despite PVSC are becoming economically competitive, they still have high cost and low light to electricity conversion efficiency. Therefore, increasing the efficiency and reducing the cost are key elements for producing economically more competitive PVSC that would have significant impact on energy market and saving environment. A significant percentage of the PVSC cost is due to the materials cost. For that, thin films PVSC have been …

Time-Variant Load Models Of Electric Vehicle Chargers, Nicole P. Zimmerman

Dissertations and Theses

In power distribution system planning, it is essential to understand the impacts that electric vehicles (EVs), and the non-linear, time-variant loading profiles associated with their charging units, may have on power distribution networks. This research presents a design methodology for the creation of both analytical and behavioral models for EV charging units within a VHDL-AMS simulation environment.

Voltage and current data collected from Electric Avenue, located on the Portland State University campus, were used to create harmonic profiles of the EV charging units at the site. From these profiles, generalized models for both single-phase (Level 2) and three-phase (Level 3) …

Power Supply For Driving High Power Leds With Wireless Control, Joshua C. Avery

Computer Engineering

This project is the design of a power supply for driving high power light emitting diodes (LEDs) with wireless control. The project is divided into two sections, the power supply for driving the LED lights, and the wireless control and fan power supply.

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 …

Veloelectric: Creating A Device That Harvests Energy From Bicycles, Austin Hall, Daniel Stohr, Tj Fox

Mechanical Engineering

Long distance mountain bikers, bike-packers, and many bikers in developing countries rely on electrical devices for safety and communication. These specific groups of people operate in areas with little to no electricity, and often times have no power to sustain their devices. The purpose of this Cal Poly senior project, VeloElectric, was to design, build, and test a kinetic energy harvester for bicycles that can be used to charge common mobile devices via USB. This senior project team created a device that attaches directly to a bicycle and uses vibrations to generate energy, which in turn powers a variety of …

The Battery Charging Hand-Powered Washing Machine “Project Uwash”, Catherine Victoria Kennedy

Honors Theses

Project UWash consists of converting the mechanical energy that goes into hand washing laundry into usable electricity. Our proof-of-concept system is composed of: an energy source (salad spinner), an energy harvester (AC generator), a regulating circuit (voltage regulator), a storage component (lithium ion batteries), and an application (charging an iPhone and USB based LED flashlight). The goal is to fully charge the LED flashlight after a one hour use and charge an iPhone to at least 50% after a 6 hour use. We were able to fully charge the flashlight in about 15 minutes but were only able to charge …

Electrical Characterization Of Nanomaterials, Chase Martin

Honors Theses

Our dependence on energy sources and depleting fossil fuel reserves are forcing the world to look for efficient and renewable sources of energy. Current renewable technology lacks the efficiency and storage capability necessary to continue our heavy reliance on energy. This project focuses on understanding the physical and electrical properties of nanomaterials for their use as super capacitors and as photovoltaic cells. Using multiple microscopy techniques on the Cascade Probe Station and Veeco Dimension V Atomic Force Microscope, local and bulk conductivity measurements were performed on Laponite RD infused polyaniline (PANI) samples synthesized by Union College Chemistry Department Students. Four …

Universal Programmable Battery Charger With Optional Battery Management System, Michael Duke Desando

Master's Theses

This report demonstrates improvements made in battery charging and battery management technology through the design of a universal programmable battery charger with optional battery management system attachment. This charger offers improvements in charge efficiency and unique battery charging algorithms to charge a variety of battery chemistries with variety of power requirements. Improvements in efficiency result from a synchronous Buck Controller topology as compared to previous universal chargers that use asynchronous Buck-Boost Converter topologies. This battery charger also surpasses current universal battery chargers by offering different charge modes for different battery chemistries. Charge modes provide the user an option between extending …

Design Of A High Powered Led Driver, Omar Renteria

Electrical Engineering

Research has shown that LED lighting products have greater energy efficiency, longer lifespans, and lower heat outputs than compared with traditional lighting technologies. An estimated growth of 45 percent per year through 2019 for the LED lighting market should provide a wider variety of LED related products to consumers. The goal of this project; to create a driving circuit that powers a set of high powered LEDs. The implementation of LEDs significantly reduces the power consumption in comparison with other types of light such as incandescent bulbs or CFLs, therefore saving the consumer money.

Design Of A Multiple Input Single Output Dc-Dc Converter For The Dc House Project, Chad Santos, Siby James

Electrical Engineering

This senior project report describes the design and further development of the MISO (multiple input, single output) circuit. The MISO circuit harnesses power from four separate renewable energy sources (hydro, solar, wind and man) and converts it into a single DC output voltage. Though this circuit has been initially designed and tested in previous years, it was only developed enough to use as a test circuit. Further implementation will allow for the MISO to be available in a more practical setting. Professor Taufik will then take the newly designed MISO circuit to implement in a house in Indonesia.

Propulsion And P.I Control Systems For Sae Aircraft, Ervin Meneses

Honors Theses

This thesis analyzes the integration and performance of a P.I control system within the SAE Aero Design Competition aircraft. This year the Union College Aero Design team will be competing in the Society of Automotive Engineers (SAE) Aero Design “Regular Class” Competition, which encompasses the design and production of a large‐scale remote controlled aircraft that must meet predetermined power and size constraints. The overall objective of the competition is to have the designed aircraft carry a maximum amount weight within a 200 feet runway while staying below a 1000W power limit. Each competitor must integrate a power limiter into their …

Sun-Tracking Solar-Powered Led Street Light, Wesley Ballar, Harrison Wong

Electrical Engineering

Street lighting is an essential utility especially in urban and industrialized areas because it provides illumination and safety for vehicles and pedestrians throughout the night. However, street lights are relatively inefficient; they consume large amounts of power from electrical grids and have predetermined operation times that are often non-optimal for the surrounding environment. The Sun-Tracking Solar-Powered LED Street Lamp is a self-sustaining device, built to replace the current lighting sources. The device features sun-tracking capabilities for maximum energy gathering and darkness recognition to establish optimal operation times. The project provides a reliable and enhanced alternative to current street lighting systems.

Current Protection For The Energy Harvesting From Exercise Machines (Ehfem) Project, Colton Crivelli

Electrical Engineering

The Energy Harvesting from Exercise Machines (EHFEM) project intends to create an exercise machine that recycles the energy expended by an athlete operating the machine by sending it to the electric grid. The work done by the user goes through a DC-DC converter and an inverter in order to prepare it for delivery to the grid. A protection circuit ensures that the inverter does not try to pull too much current from the DC-DC converter. The project implements a current protection system that ensures the system doesn’t experience an overcurrent condition.

Voltage Protection System For Ehfem Project, Calvin Abshier, Calvin Xu

Electrical Engineering

The EHFEM project aims to convert the energy generated by exercise in a gym to electrical power and transport said energy to the grid. At the top level, this project includes several components including: a voltage and current protection system, a DC-DC converter, and an inverter. This project improves upon past voltage protection systems [1] [2]. The DC-DC converter takes the user-generated energy from the elliptical trainer and passes it to the grid. The user can generate voltage spikes upwards of 100V, far above the current DC-DC converter’s maximum limit. The voltage protection circuit sits between the energy harvesting machine …

The Dc House Project: Electrical System Design & Construction, John Bradley

Electrical Engineering

This project entails the design and assembly of the photovoltaic system, switchboard panel enclosure, and battery enclosure for the DC House’s main electrical system. The intended purpose of this project is to provide the electrical framework necessary for future students to easily modify and add to this rendition of the DC House. The principle design implements a variety of renewable energy sources, however this senior project only uses solar power in order to maintain a manageable scope. Each of these renewable energy sources are stepped down to a voltage of 24V and input to a Multi Input Single Output DC …

The Zephyr Charge: A Wind-Powered Usb Charger, James Dean Carson, John Pina Lopez Iii

Electrical Engineering

The Zephyr Charge project is to design and build a cell phone charger using a small wind turbine generator that can be useful to the fishermen community, namely fishermen of third world countries. The generator will output to USB for ease of charging capability. The size of the whole system should be light enough to move around, and the turbine itself will be mountable onto an edge of a wall. The goal of this project is to design and build a compact and easy to use cell phone charger, which is also efficient.

In order to be a practical product, …

Smaller And More Efficient Ac To Dc Converter For Laptops, Jacob Dye

Electrical Engineering

The goal of this project is to create a laptop charger that does not have a big box converter. This will be better for the user because the big box converter always gets in the way. This will be accomplished by designing a cable that has several smaller components in it. Figure 1 shows a high level block diagram of how this design could look. The cable must still be able to handle all the power requirements of a laptop charger: to convert high voltage AC to the DC charging voltage. It must also be able to vary the current …

Enterprise Smart Outlet, David Faltmier, Matthew Mcgill, Luke Stencel

Electrical Engineering

The purpose of our senior project, Enterprise Smart Outlet, is to create an electrical outlet which will allow enterprise users to monitor and change their power consumption habits on a large scale. The initial goal of this project is to allow consumers to see their power consumption per outlet in real time, and then using that information conform their future habits to help them conserve electrical energy, and more importantly, money. Three requirements for our project to meet our initial goal are, the outlet will work in a standard electrical outlet and be completely compatible with current electrical standards, the …

Sel-311l Overreaching Impedance Pilot Protection Laboratory, Brandon Van Loon

Electrical Engineering

The objective of this senior project is to protect a three terminal transmission line during fault conditions using the SEL-311L microprocessor based relay and communication assisted permissive over-reaching transfer trip protection (POTT). The SEL-311L’s directional distance elements are programmed to trip on internal faults while faults external to the zones of protection are ignored. Upon sensing a fault condition, the relay issues a trip command to the local breaker and a permissive key for tripping to the remote relay via fiber optic communication. When a permissive key is received and all other permissive conditions have been satisfied, the remote relay …

Department Of Energy Solar Decathlon 2015, Dante C. Carrillo, Dion A. Celebrado, Jenna I. Denhaan, Christian F. Ferrer, Simon D. Hauser, Audrey L. Rempher, Joseph H. Rohrer, Casey S. Smith

Electrical Engineering

The goal of the Department of Energy (DOE) Solar Decathlon 2015 project is to design, build, and operate a zero-net energy solar-photovoltaic (solar-PV) powered residence. It is an international competition taking place in the fall of 2015 in Irvine, California. The design needs to be attractive, energy-efficient, innovative, and affordable. The Cal Poly team includes students from a variety of majors, including Architecture, Mechanical Engineering, Electrical Engineering, and many more. The different disciplines need to work together to create a functional and cohesive design. For our senior project, we have designed the electrical systems in the home, including the power, …

The Electric Reel For Soccer Fields, Stephen Taylor

Electrical Engineering

Painting a soccer field consumes too much time. The process of reeling the string after laying out string along the field needs to improve. As a result, my project addresses improvements in how the workers retrieve the string through the production of an electric reel. This electric reel allows the worker to have control of the speed, direction, and on/off state of the device. Direction control allows the user ability to reel and unwind the string. Variable speed allows the user to control how fast the reel unwinds and reels the string. The device gathers string in an orderly manner …

Adaptive Automotive Lighting Systems, Marc W. Haeberlin

Master's Theses

Over the past few years, the use of LEDs within the automotive and avionic industries has increased due to their high efficiency, durability and wide range of light brightness. As the use of LEDs within these industries grows, a need for reliable, high performance drivers becomes more relevant. Companies are implementing LEDs for applications involving adaptive lighting or simple dimming features. This thesis shows implementation of various non-isolated analog converters integrated with digital dimmers to achieve these adaptive lighting systems. Adaptive lighting systems involve reading an input from an external source (brake pedal or steering wheel) and changing the brightness …

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 …

Bulk Heterojunctions In Photovoltaic Devices, Ondrej Edward Dyck

Doctoral Dissertations

Current solar cells, on the market today, have little room for improved efficiency or cost reduction. Part of this is due to the costly manufacture of high purity silicon and the current fabrication methods for solar cells. Solution processable solar cells would mark a great stride forward to cost reduction. If such cells can be demonstrated to be efficient enough and stable enough it would be a turning point in history. However, solution processable devices still need much work before they can compete in the market. This text addresses characterization problems in the TEM, covers a study dealing with optimization …

Saturable Reactor For Power Flow Control In Electric Transmission Systems: Modeling And System Impact Study, Marcus Aaron Young Ii

Doctoral Dissertations

A Saturable Reactor for Power Flow Control (SRPFC) is a novel application of a concept well known to electronics and power electronics engineers that provides continuous modulation of line reactance by controlling the magnetization in a ferromagnetic core. The novelty of the SRPFC is the target application, which is power flow control in meshed electric power networks. Modulation of the line impedance occurs by altering the current in a DC winding to control the magnetization of the ferromagnetic core, thereby varying the reactance of the AC winding. The deployment of power system equipment, like SRPFC, requires careful planning and study …

Implementation Of Natural Switching Surface Control For A Flyback Converter, Ethan Storm Williams

Electrical Engineering Undergraduate Honors Theses

The flyback converter is an extremely common topology used for DC/DC power conversion. Widely used methods to control the flyback converter include voltage mode and current mode controllers. More recently, sliding mode control has been developed for the flyback converter. While these control methods may be considered adequate, the Natural Switching Surface (NSS) sliding mode control method detailed in this thesis presents a more robust controller. NSS control eliminates the effects presented from variations in components and design as well as minimizes the effects from external disturbances. This thesis steps through the complete design and implementation process of a NSS …

Hybrid Fuzzy-Pid Controller For Buck-Boost Converter In Solar Energy-Battery Systems, Karime Farhood Hussein

Masters Theses

In the present work, we propose a hybrid fuzzy PID control system to prevent overshoot and oscillations in DC-DC buck-boost converter for solar-battery system. We design and simulate a PID, a Fuzzy logic controller, and hybrid fuzzy PID control system to stabilize the output voltage of the buck-boost converter. The performance results using dynamic response of all of these controllers in terms of rise time, overshoot, peak time, and voltage oscillation are presented. The simulation results support the validity and advantages of the hybrid method.

Top-Down Aluminum Induced Crystallization For Photovoltaics, Seth Daniel Shumate

Graduate Theses and Dissertations

Passivating silicon solar cell surfaces is critical to fabricating very high efficiency and low cost photovoltaic devices. The sun-facing surface of the solar cell, known as the emitter, is particularly important when designing a solar cell. This work focused first on an alternative method of forming the emitter of silicon solar cells, and secondly on a method for improving the surface passivation of both these non-traditional and standard n-type solar cells.

Top-down aluminum induced crystallization (TAIC) was used for forming a polycrystalline silicon layer from amorphous silicon using aluminum to catalyze the crystallization at much lower temperatures than otherwise possible. …

Evaluating The Level Of Harmonic Distortion In A Typical Distribution Feeder, Wessen S. Bogale

UNLV Theses, Dissertations, Professional Papers, and Capstones

Steady-state analysis of electrical power systems is largely based on linear and sinusoidal AC circuits which allow the concept of impedance, phasors and well-defined power quantities (i.e., real, reactive and apparent powers). In reality, however, the electric load which was once composed of linear elements (e.g., induction motors, incandescent lighting, etc …) is becoming more and more nonlinear due to the wide-spread use of electronic components such as fluorescent lighting and variable-frequency drives that power the majority of electric motors. As a consequence, the current drawn by such devices is often distorted, thus containing a number of high frequency harmonics …

Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer

Graduate Theses and Dissertations

With the increase in energy demand by the residential community in this country and the diminishing fossil fuel resources being used for electric energy production there is a need for a system to efficiently manage power within a residence. The Smart Green Power Node (SGPN) is a next generation energy management system that automates on-site energy production, storage, consumption, and grid usage to yield the most savings for both the utility and the consumer. Such a system automatically manages on-site distributed generation sources such as a PhotoVoltaic (PV) input and battery storage to curtail grid energy usage when the price …