Power and Energy Commons^™

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.

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.

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, …

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.

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.

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 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 …

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.

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 …

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 …

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 …

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 …

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 …

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.

Cal Poly Electrical Distribution Coordination And Short Circuit Analysis, Alexander Gomez, Kaylynn Rothleder

Electrical Engineering

The purpose of this project is to maintain the California Polytechnic State University Electrical Distribution System by performing short circuit and protective device coordination studies for the Baker Science Building. When a short circuit arises in a system, there is no finite way in telling what protective device will be tripped, which can cause outages, arc flashes and electrical explosions. The best way in determining the outcomes of these occurrences are to perform precise simulated reports. To output these reports, design and analysis of the single line through a commercialized software, Power Tools for Windows (SKM) was used. To name …

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. …

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 …

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 …

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 …

Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

The success of Wireless Sensor Networks is heavily constrained by its reliance on storage technology like batteries, which are a finite resource. Whilst the number of transistors in an IC doubles every 18 months, the energy density of batteries is relatively flat during the same time period. This is a key challenge in leveraging the Internet of Things on trains.

The gravity of this problem is increased by an order of magnitude when the network is to be scaled up to hundreds or thousands of nodes. Comprehensive research and development efforts have been devoted to building ultra-low power sensors. These …

Researches On In-Situ And Ex-Situ Characterization Techniques In Lithium Batteries, Wen-Jun Li, Jie-Yun Zheng, Lin Gu, Hong Li

Journal of Electrochemistry

Electrochemical performance of Lithium batteries is directly linked to interfacial transports, reactions and storing behaviors of electrons and ions at bulk-surface interfaces. It is extremely important to conduct evolution studies from atomic level to macro level in electron structures, crystal structures, microstructures and morphologies, chemical compositions and physical properties of battery materials at equilibrium and nonequilibrium in order to understand various structure-performance relations in lithium ion batteries. Advanced in-situ and ex-situ characterization techniques have been used widely to clarify scientific and technological problems in lithium batteries. This paper summarizes our efforts on battery researches using various experimental techniques, including in …

Recent Research Progress For Non-Pt-Based Oxygen Reduction Reaction Electrocatalysts In Fuel Cell, Ping Song, Ming-Bo Ruan, Jing Liu, Guang-Jun Ran, Wei-Lin Xu

Journal of Electrochemistry

The expensive Pt-based catalyst suffers from its susceptibility to time-dependent drift, methanol crossover, and carbon monoxide (CO) deactivation, which will block the large-scale commercial application of fuel cells. It is, therefore, necessary to develop efficient, low-cost, highly stable non-precious metal oxygen reduction reaction (ORR) catalysts with high catalytic performance. Here, we will pay attention to the research progress of non-precious metal and heteroatom-doped (N, B, P, S, F) metal-free ORR catalysts. Importantly, we mainly focus on the work developed by Xu’s group with the Fe-based non-precious metal and F/NF-doped metal-free ORR catalysts. The purpose of these works is to improve …

Research Progress Of Mn-Based Lithium-Rich Cathode Materials For Li-Ion Batteries, Luo-Zeng Zhou, Qun-Jie Xu, Wei-Ping Tang, Xue Jin, Xiao-Lei Yuan

Journal of Electrochemistry

With rapid development of new energy industry like electric vehicles and energy storage station, these fields highly demand the next generation of high performance Li-ion battery systems with stronger energy density, higher power density, and longer cycling life. Lithium-rich Mn-based cathode materials, xLi₂MnO₃·(1-x)LiMO₂(M=Mn, Co, Ni...), have become the hot topic and drawn attentions of scholars worldwide because of their high reversible capacity exceeding 240 mAh·g^-1, excellent electrochemical properties, and low cost, which makes them most promising cathode material candidates for next Li-ion battery system. The cathode material Li[Li_0.2Mn_0.54Ni …

Preparation And Properties Of Binary Oxides CoXCr1-XO3/2 Electrocatalysts For Oxygen Evolution Reaction, Tai-Lai Yang, Wen-Yan Dong, Hui-Min Yang, Li Zhang, Zhen-Hai Liang

Journal of Electrochemistry

Binary metal mixed oxides of Co and Cr with nominal compositional formulas, Co_xCr_1-xO_3/2 (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0), were obtained by thermal decomposition method. The morphologies, crystal forms and valence states of the catalyst powders were analyzed by SEM, XRD and XPS, respectively. And the electrochemical properties, overpotentials and stabilities of Co_xCr_1-xO_3/2 electrodes for oxygen evolution reaction (OER) in an alkaline solution were evaluated by linear sweep voltammetry (LSV), staircase voltammetry and chronoamperometry, respectively. The results indicated that the mixtures of Co₃O₄ and eskolaite-Cr_{2 …}

Synthesis And Electrochemical Properties Of Cnts/V2O5 Hollow Microspheres, Liang Hao, Lai-Fa Shen, Jie Wang, Jia-Jia Zhu, Xiao-Chen Zhao, Xiao-Gang Zhang

Journal of Electrochemistry

The carbon nanotubes/vanadium oxides (CNTs/V₂O₅) hollow microspheres (VOC) were prepared via solvothermal process. The effects of the ratio for CNTs to V₂O₅ on the morphologies, structures and electrochemical performances were systemically investigated. The results indicate that CNTs dramatically enhanced the rate performances of VOC composite electrodes. When the ratio of CNTs is 7.1%, the VOC composite electrode exhibited the best electrochemical performance, which delivered a specific capacitance of 346 F·g^-1 at 0.5 A·g^-1 and maintained 75% at 8 A·g^-1 in 5 mol L^-1 LiNO₃. A hybrid capacitor …

A Platinum-Hydrogen Reference Micro-Electrode For All Vanadium Redox Flow Battery, Zhi-Bin Lin, Yan-Qing Dong, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

A platinum-hydrogen reference micro-electrode was made with electroplating Pd on the surface of Pt wire and then coating anion membrane material. This reference electrode was built-in the porous electrode of the all vanadium redox flow batteries (VRFB), and monitored the charging /discharging and self-discharging of the VRFB. The results indicated that the capacity fading of VRFB occurred due to the graduate reduction of V(IV) active species in the electrolyte and the accumulation of V(V) in the positive electrode, leading to nonequilibrium of active species between the positive and negative electrodes.

Porous Co3O4 Hollow Nanospheres Cathode Catalyst For High-Capacity And Long-Cycle Li-Air Batteries, Tong Liu, Na Li, Qing-Chao Liu, Xin-Bo Zhang

Journal of Electrochemistry

In this paper, a high specific surface area of porous Co3O4 hollow nanospheres was successfully synthesized via hydrothermal carbonization at 140 °C, followed by calcination using cobalt nitrate hexahydrate (Co(NO3)2·6H2O), hexamethylenetetramine (HMT), sucrose, and sodium citrate (Na3C6H5O7). The porous Co3O4 hollow nanospheres consisted of nanoparticles with high specific surface area of mesoporous structure, and could provide active reaction sites for OER and ORR. When used as lithium-air battery cathode catalyst, the Co3O4/Super P (SP) electrode exhibited excellent cycle performance, resulting in high capacity and long life of lithium-air batteries.

Syntheses And Electrochemical Performances Of Li4Ti5O12 Anode Materials For Lithium Ion Battery, Yong-Long Zhang, Xue-Bu Hu, Yao-Qiong Wang, Dong-Hai Huang

Journal of Electrochemistry

Series of spinel lithium titanate (Li₄Ti₅O₁₂) materials were synthesized by one-step solid-state reaction using lithium acetate and TiO₂ as raw materials under different temperatures (750/800/850 °C) and atmospheres (N₂/air). The as-prepared Li₄Ti₅O₁₂ materials were investigated by thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, cyclic voltammotry and charge-discharge test to analyze their crystal structures, microstructures and electrochemical performances. The results show that the Li₄Ti₅O₁₂（L-800N）material obtained at 800 °C under nitrogen atmosphere exhibited better electrochemical performance and smaller particle size. The initial …

Electrochemical Conversion Reactions And Their Applications For Rechargeable Batteries, Ting Li, Han-Xi Yang

Journal of Electrochemistry

Electrochemical conversion reactions have received considerable interest as a new redox mechanism for constructing high capacity electrodes of rechargeable batteries. Without strict restrictions on the crystalline structure of the host lattice and the size of the associated ions, conversion reactions can take place in a variety of different metal compounds with different metal cations and deliver much higher reversible capacities through full utilization of all the oxidation states of the transition-metal compounds, opening up a new avenue for developing high capacity materials of rechargeable batteries. This paper briefly reviews the state of the art and challenges of conversion electrodes and …