Electrical and Electronics Commons^™

Grid Voltage Unbalance And The Integration Of Dfig’S, Joseph Kearney

Doctoral

Double-fed induction generators (DFIG’s) became the predominant generator installed for wind generation applications in the mid 1990’s. Issues pertaining to the operation and control of DFIG’s subsequently became apparent, particularly in weak areas of the grid network. Ironically weak areas of the grid tend to be where the average wind speed is high and the usual location of wind farms. One of the issues that emerged was the quality of the voltage in the network at the point of common coupling (PCC) with the DFIG’s. An important issue is the question of voltage unbalance at the PCC. As part of …

Digital Microfluidics As A Reconfiguration Mechanism For Antennas, Yasin Damgaci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The properties of conventional antennas are fixed by the initial design and cannot be changed. A reconfigurable antenna, on the other hand, can dynamically change its properties, and it can adjust its behavior for a given propagation condition. This dissertation work concentrates on novel reconfiguration technologies, including design, microfabrication, and characterization aspects with an emphasis on their applications to multifunctional reconfigurable antennas. In the literature, reconfigurable antennas have made use of various reconfiguration techniques. The most common techniques utilized revolved around switching mechanisms. Other techniques such as the incorporation of variable capacitors, varactors, and physical structure manipulation surfaced recently to …

Resource-Induced Voltage Flicker For Wave Energy Converters – Assessment Tools, Fergus Sharkey, Joe Macenri, Elva Bannon, Michael Conlon, Kevin Gaughan

Articles

For wave energy converters, the input resource has a typical period of 5–20 s depending on the site location and dominant seastates. Wave energy converters generally produce mechanical power twice per wave cycle and therefore depending on the storage available, the electrical power output has half the period of the input resource. These regular power changes induce a voltage change at the point of connection (POC) which is proportional to the amplitude of the power change and at the same frequency. Therefore the coupling of the input resource to the output power of a wave energy converter will cause voltage …

High Voltage Direct Current Energy Transmission Using Modular Multilevel Converters, David Alejandro Guzman Pinzon

Graduate Theses and Dissertations

This thesis focus on high voltage direct current (HVdc) energy transmission using modular multilevel converter (MMC) based terminals. It provides a brief comparison between different HVdc technologies, focusing on voltage source converters (HVdc-VSC) with the MMC-based terminal emerging as the topology of choice for ratings less than 1 GW. The controllers for a two-terminal HVdc-link are analyzed and Matlab/Simulink^TM simulation models are presented. The simplified models and full Matlab/Simulink^TM based model are used to select the gains for the MMC controllers. Simulation results carried out on the full model validated the proposed methodologies. A new control technique that …

System Design And Motion Artifact Removal Algorithm Implementation For Ambulatory Women Ecg Measurement System:E-Bra System, Hyeokjun Kwon

Graduate Theses and Dissertations

Cardio Vascular Disease (CVD) leads to sudden cardiac death due to irregular phenomenon of the cardiac signal by the abnormal case of blood vessel and cardiac structure. For last three decades, there is an enhanced interest in research for cardiac diseases.. As a result, the death rate by cardiac disease in men has been falling gradually compared with relatively increasing the death rate for women due to CVD. The main reason for this phenomenon is due to the lack of seriousness to female CVD and different symptoms of female CVD compared with the symptoms of male CVD. Usually, because the …

Design And Fabrication Of Inverter And Rectifier Modules For Indirect Matrix Converter Applications, Saikishore Talakokkula

Graduate Theses and Dissertations

In power converter applications, silicon carbide (SiC) power semiconductor devices are preferred over their silicon counterparts due to many advantages such as wide bandgap, high junction temperatures and low on-state resistance. The SiC devices provide reduced conduction and switching losses. Due to the above mentioned advantages the power conversion efficiency of SiC devices is better compared to that of silicon (Si) devices.

This thesis studies the implementation of 1200V/17A Normally-off SiC JFETs for an indirect matrix converter (IMC) application. A discussion on the parasitic inductance optimization is presented based on the electromagnetic simulation results extracted from the Ansoft Q3D extractor. …

2-Dimensional Personal Motion Energy Harvester For Low Power Electronics, Manuel Gutierrez, Sean Scott, Dimitrios Peroulis

The Summer Undergraduate Research Fellowship (SURF) Symposium

In a lab, it becomes crucial to have a way to monitor that lab workers aren’t exposed to too much radiation. Such a device that detects this should have an energy harvester so that batteries aren’t required. The need for an energy harvester that generates power from a user’s movements in 2 dimensions is needed. This energy harvester is needed to power a radiation monitor. An energy harvester that generates power based off movements in 2 dimensions was developed. The energy harvester was created through a series of prototypes. Each prototype was built from a CAD drawing and a stereolithography …

Advanced Circularly Polarised Microstrip Patch Antennas, Adam Z. Narbudowicz

Doctoral

The thesis describes outcomes of research on advanced circularly polarised antennas. The proposed designs are intended for integration into small mobile devices, therefore low profile and easy manufacturability are key parameters, along with good CP radiation properties. The designs were validated by simulation and measurement, and are also backed by theory and design guidelines. The primary focus is on the development of planar omnidirectional circularly polarised antennas, which are fabricated using multilayer PCB techniques and thus are lightweight and cost-efficient. Unlike in classical microstrip patch antenna designs, the groundplane of the proposed antenna was substantially reduced. This helps to achieve …

Gas Leakage Detection System (Glds), Daudi Simbeye

Tanzania Journal of Engineering and Technology (TJET)

This paper mainly focuses on the detection of gas leakage and providing security when the user is around or away from home. The system is Short Message Service (SMS) based and uses wireless technology for providing security against gas leakage to users hence cost effective and more adaptable. The system comprises of sensors for detecting gas leak interfaced to microcontroller that will give an alert to user whenever there is a gas leakage, display warning information by using Liquid Crystal Display (LCD), sending SMS to the user for notification wherever he/she might be and turning off electric power with the …

Lunalight - Bringing Light To The Expanding World, Gabriela M. Igel, Daniel J. Patrick, Kimberley M. Smith

Materials Engineering

The LunaLight, a solar rechargeable light and cell phone charger, addresses the lack of access to electricity faced by 1.4 billion of the world’s population (International Finance Corporation). The LunaTech team has developed a product that is bright, simple, compact, versatile and competitive with existing products. Through a partnership with the non-profit organization One Million Lights, LunaTech has improved a previous team’s design to address user feedback, concerns of durability, and manufacturability.

The LunaLight design includes a 5 component plastic housing held together by 4 screws, a surface mounted PCB, a lithium-ion (Li-Ion) battery, one high-brightness LED, a solar panel, …

Cubesat Launch Sequencer, Billy Beecher

Electrical Engineering

I am working with the Naval Postgraduate School to develop a low cost CubeSat launch sequencer for NPSCuL that is designed to operate in low Earth orbit. The system will be capable of providing programmable delays with a minimum delay of one second to a maximum delay of five minutes. Delays must be accurate to within ± 10% or within one second, whichever is less. After the delay, the system will provide the necessary launch signal. To ensure protection from radiation, the system will feature triple redundancy and voting logic stages to ensure that the proper signal is propagated.

Broadband, Rugged, High Linearity, Low-Noise Amplifier, Shane Smith

Electrical Engineering

This report examines the application of a low-noise amplifier module for a Global Positioning System (GPS). This low-noise amplifier module helps allow the carrier signal to get the amplification needed to give a smoother analog to digital conversion. However, the frequency range of the GPS spectrum reaches up to 1.6GHz, where component noise becomes an issue and can create a disrupted signal. This low-noise amplifier needs to create a reasonable gain, while achieving a low noise figure. An amplifier with high gain and low noise figure becomes difficult because they create a design trade-off, higher the gain brings higher the …

Alternative Wheelchair Control System, Jessica Hendricks, Tara Keigharn

Electrical Engineering

We geared this project towards assisting an individual with limited[1] motor function to operate a wheelchair. The product targets individuals who find use of a joystick is ineffective or painful. We focused our design on the wheelchair bought from Adaptive Driving Systems (Driving, 2013); but ultimately we would like to field a final product capable of applying to any electric wheelchair. Our goal: a person to operate the electric wheelchair using sensors that transmit a translation of an individual’s hand movement through a wireless transmission to a microcontroller installed on the wheel chair that then controls the wheelchair’s movement. …

High Frequency Open Air Optical Communication System, Alexander C. Wolff

Electrical Engineering

The goal of this project is to create a wireless optical communication system that operates at high frequencies (up to 3 GHz). The system will function by taking a digital electric input signal, converting it to a photonic signal, recovering the signal at the other end of a short distance (~1 foot) and converting it back into a digital signal. Unlike the more common fiber-optic data transmission systems, this system will transmit light through air, instead of fiber, as its medium. Doing so will have the benefits of a wireless system combined with the benefits from an optical system, including …

Cal Poly Wind Power Research Center Power Regulator, Ricardo Rodriguez, Steven Bounchareune

Electrical Engineering

Through funding from the California Central Coast Research Partnership (C3RP) the

CPWRC, led by Dr. Patrick Lemieux, has erected a horizontal axis wind turbine (HAWT) at the

Cal Poly Escuela Ranch site EL04. With the help of Dr. John Ridgely and Dr. Art MacCarley, the team has implemented a controller that delivers the power being generated by the turbine to a resistor bank which maintains a safe working speed for the turbine. The authors objectives for this project are to (1) become familiar with the operation of the turbine, (2) develop an AC-DC converter that regulates the output of the …

The Visual Representation Of Sound For The Hearing Impaired, Jonathan Brophy

Electrical Engineering

There are many difficulties that arise when one is faced with a hearing disability. New applications of advancing technology have the potential to enable designs capable of assisting the hearing impaired with the ability to see sound. This project seeks to provide a user with a visual representation of loud noises detected using small directional microphones. The microphones determine the location of the sound above a set decibel level and a microprocessor determines the approximate location of the sound source and displays a vertical colored bar on a video image in the direction of the noise using virtual reality glasses. …

Pscad Modeling Of One-Cycle Control Var, Andre Keir Azares

Electrical Engineering

Voltage support has been a common problem utilities have faced for many years and although there exists many solutions, the advent of renewable energy devices and electric vehicles make the problem of voltage support an even greater challenge today. The increasing use of electronic devices by consumers also increases the magnitude of dealing with voltage support. A promising new solution to voltage support is seen in One Cycle Control, a new control method that uses a nonlinear feedback technique on power electronics to produce high quality sine waves with fast dynamic response. This control paradigm is seen in its application …

Multiple Input Single Output (Miso) Tablet/ Phone Charger, Kevin Wong

Master's Theses

This thesis entails the design and implementation of a multiple input single output (MISO) DC-DC converter using the flyback topology to charge tablets/ smartphones or any USB powered portable device. The MISO converter will enable the use of various renewable energy sources such as a solar panel/ rechargeable battery combination, bicycle dynamo, hydroelectric power, and wind turbine. This paper will cover the design, simulations, and test results of the MISO converter. The flyback topology was chosen due to its low part count and its efficiency at low power. The proposed converter has a nominal 12V input to output USB 2.0 …

Cal Poly Brocade Challenge 2013, Chandler Morehardt, Alexa Coburn, Juan Silva, Kerry Sun, Greg Wang, Raul Chagoya, Jd Torres

Architectural Engineering

No abstract provided.

Multiplicative Feedback Audio Distortion Circuit, Colton Parsons

Electrical Engineering

This circuit aims to distort an audio signal input in a novel and aesthetically pleasing manner. When it comes to the timbre of a note, even harmonics generally sound better than odd harmonics. Most forms of audio signal distortion (usually for electric guitar) primarily add odd harmonics to a signal, as this is easily accomplished by clipping the waveform. This project instead utilizes a signal multiplier in a feedback loop, with one multiplier input coming from the circuit’s input, and the other from the multiplier’s own output. This process creates even harmonics. A delay line is placed in the loop, …