Electrical and Electronics Commons^™

Zero Voltage Switching Hybrid Voltage Divider Converter, Timothy Jeong

Master's Theses

This project proposes a new hybrid voltage divider DC-DC converter that utilizes switching capacitors and inductors to produce zero voltage switching (ZVS) at the turn on state of its switches. By achieving ZVS, the switching losses are significantly reduced; thus, increasing the overall efficiency of the converter at various loads. The goal for this thesis is to perform analysis of the operation of the converter, derive equations for sizing the main components, and demonstrate its functionality through computer simulation and hardware prototype. Results of the simulation and hardware testing show that the proposed converter produces the desired output voltage while …

First Order Self-Oscillating Class-D Circuit With Triangular Wave Injection, Matthew J. Carroll

Master's Theses

An investigation into performance improvements to the modulator stage of a class-D amplifier is conducted in this thesis. Two of the standard topologies, namely class-D open-loop pulse-width modulation (PWM), and the improved self-oscillating feedback system are benchmarked against a topology which includes both a hysteretic comparator in a feedback loop and triangle wave injection. Circuit performance is analyzed by comparing how the triangle injection circuit handles known issues with open-loop and self-oscillating circuits. Using this analysis, it is shown that the triangle injection topology offers an improved power supply rejection ratio relative to open-loop PWM and reduces distortion generated by …

Design And Modeling Of A Distributed Network For The Dc House Project, Lauren N. Rotsios

Master's Theses

This thesis covers the design and simulation of a model for a distributed network of DC Houses in MATLAB Simulink. The model will allow for sharing of power between houses within the network. The developed model consists of five separate DC House branches with local power generation. Each branch consists of a PV MPPT charge controller subsystem, a resistive load, and a bidirectional buck-boost converter subsystem. The high voltage side of every bidirectional buck-boost converter is connected together through the transmission line at a single high voltage DC bus. The performance of the individual components of the model is verified …

Scalable Cognitive Radio Network Testbed In Real Time, Kevin Z. Yu

Master's Theses

Modern society places an increasingly high demand on data transmission. Much of that data transmission takes place through communication over the frequency spectrum. The channels on the spectrum are limited resources. Researchers realize that at certain times of day some channels are overloaded, while others are not being fully utilized. A spectrum management system may be beneficial to remedy this efficiency issue. One of the proposed systems, Cognitive Radio Network (CRN), has progressed over the years thanks to studies on a wide range of subjects, including geolocation, data throughput rate, and channel handoff selection algorithm, which provide fundamental support for …

Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu

Master's Theses

The processors and digital circuits designed today contain billions of transistors on a small piece of silicon. As devices are becoming smaller, slimmer, faster, and more efficient, the transistors also have to keep up with the demands and needs of the daily user. Unfortunately, the CMOS technology has reached its limit and cannot be used to scale down due to the transistor's breakdown caused by short channel effects. An alternative solution to this is the FinFET transistor technology, where the gate of the transistor is a three dimensional fin that surrounds the transistor and prevents the breakdown caused by scaling …

Power Line Coupling Power Supply Design, Janine Gian Christii C. Darato, Jeni K. Kawate, Nicholas A. Marta

Electrical Engineering

In this project, a power supply was designed for a startup company, Perch Sensing, to detect wildfires with the use of distributed sensors across power lines. The purpose of the power supply is to provide 15W of power to a microcontroller, which controls the sensor nodes. The power supply hangs from power lines and draws energy by inductively coupling to these lines. Our design starts with a current transformer that steps down the current from the power line, which is fed into a shunting mechanism as a safety precaution when the load is absent, then to the power supply itself. …

Buck Converter With Voltage Foldback Protection, Fabian Aaron Enriquez, Pedro Rincon Rosales

Electrical Engineering

In this work, we implemented the idea of current foldback protection onto a buck converter. Current foldback protection essentially helps reduce the power dissipation which may be caused by a short circuit or overload scenario. To achieve the goal of this project, we used a combination of comparators, operational amplifiers and MOSFETs to create a current foldback sub controller. This controller would then serve as a feedback device between the output of the converter and the main controller to detect if a fault condition has occurred. Following the design, we performed simulation of the current foldback controller using PSpice and …

Tractor Hacking, Jin Huang, Kyle B. Kesler

Electrical Engineering

Tractor hacking arose from tractor owners' desire for full control over the tractors they purchase. Tractor manufacturers set strict security on the electrical components of their tractors, making it difficult for tractor owners to diagnose and monitor their tractors on their own. The UltraBlue Tractor Hacking project is a solution to this problem, allowing tractor owners to perform diagnostics and monitor the equipment they purchased without having to go through dealerships. From talking to farmers, we found that they valued a diagnostic tool that allows for clearing and resetting Diagnostic Trouble Codes (DTCs), viewing diagnostic data pertaining to a specific …

Portable Ventilator, Bradley C. Weeks, Jack W. Brewer, Sanders Sanabria

Electrical Engineering

The current COVID-19 pandemic has heavily impacted the healthcare system in the United States and elsewhere. The need for patients to have access to a hospital with a ventilator along with a shortage of ventilators for recovery and at-home care as a result of minimal hospital vacancy for patients has been greatly stressed. The presented problem is both an unmet demand and supply of portable and effective ventilators. Existing ventilators have many shortcomings that should be addressed: size, weight, cost, and complexity of current ventilators confines users to stay in a medical facility whilst being monitored by professionals. This both …

Survey And Design Of Microwave Low-Noise Amplifiers, Omri Yaari, Pavin Virdee

Electrical Engineering

This project is a contest entry in the Wide In-band Receiver area of the 2020 International Microwave Symposium, 5G Low Noise Amplifier Competition [1]. The project includes RF transistor selection, single, two-stage, and cascode models, and RF parameter optimization to maximize the IMS Competition figure of merit along with a supplemental figure of merit [2]. 5G technologies (used in cellphones, IoT, etc.), first introduced in 2018, are on the rise in current society. Fifth generation hardware requires extended capabilities in comparison to 4G (5-20MHz bandwidth EU: 0.6-2.6GHz), including the newly allocated sub 6GHz frequency bands (EU: 3.4-3.8GHz) and wider bandwidth …

Led-Based Solar Simulator, Jonathan E. Honrada

Electrical Engineering

Solar simulators are great laboratory tools that help users conduct tests with solar cells indoors. Conventional solar simulators typically use xenon arc bulbs as a light source, which can have considerable disadvantages. Recent projects have sought to design and implement LED-based solar simulators, as they are more power-efficient, inexpensive, and durable.

Based on these advantages, the goal of this project is to create an LED-based solar simulator that can replicate the characteristics of solar light, but also be tunable with controls. This broadens the testing capabilities of the device, allowing users to conduct tests with more narrow spectrums of light …

Pilltank, Lucas Chang, Hayden Tam, Aaron Teh, Krista Round

Electrical Engineering

Imagine an elderly family member, going through their daily routine of taking their pills. They find their pill box; however, they are having trouble identifying all the pills in there. Is there a name on the tablet? Can they read what it says? Do they just trust that the medication in their box is correct? How can they properly take care of themselves if they can not even confirm that what they are taking is the right medication? To combat this issue that many face, we present PillTank.

To decrease the risk of consuming the wrong medication, PillTank identifies the …

Development Of A Low-Cost Hybrid Music Synthesizer, Spencer Rollins Drewry

Electrical Engineering

Until recently, affordable music equipment has always been seen as “budget”, providing a poor user experience. Inexpensive equipment was plagued with audible noise, signal integrity issues, and convoluted user interfaces. Companies like Teenage Engineering have proven that this does not have to be the case, in 2019 introducing their "Pocket Operator” series for $89. Due to the modern availability of low cost, high quality, consumer off the shelf [COTS] analog and digital components as well as creative engineering, the quality of inexpensive audio equipment has increased significantly. Despite these industry advances, the market is relatively small and shows a great …

Dc-Dc Buck Boost Converter Using The Lt8390 Controller And Gan High Electron Mobility Transistors, Juan Manuel Urbano Jr, Brian Thongchai Keokot

Electrical Engineering

California Polytechnic State University, San Luis Obispo’s ongoing Energy Harvesting from Exercise Machines (EHFEM) project creates a sustainable energy source by converting physical exercise from exercise machines into renewable electricity. Implementing energy harvesting technology into the Recreation Center’s exercise machines helps Cal Poly make progress on its goal of carbon neutrality by 2050 [1]. An improvement to the system with new technology increases Cal Poly Recreation Center’s ability to save money and improve sustainability.

The focus of this project improves the design of Nicholas Serres, who used the LT8390 controller in his buck boost DC-DC converter [2]. This project improves …

Wildfire Early Detection System (Weds), Mason Mciver, Vincent Liang, Jeanreno Racines

Electrical Engineering

With climate change causing an increase in temperature over the past several decades, wildfires have been burning hotter and moving quicker leaving a trail of destruction in their path. Detecting a wildfire early allows firefighters to respond efficiently and effectively to ensure containment. With the rise of advanced computer vision and algorithms, autonomous systems can be used to monitor and report any fire activity. Having multiple devices spread out across a large area will allow first responders to map out the fire location and track the fire. By utilizing smart technologies, property damage can be minimized and residents living in …

Miniaturized Ultraviolet Imager High Voltage Power Supply, Nicholas Palmer, Jason Thomas Heil

Electrical Engineering

Sending satellites into orbit becomes exponentially more expensive with weight and size, so designing high-voltage DC-DC converters that can achieve kilovolt level outputs in a small form factor is crucial to reducing costs. The Miniaturized Ultraviolet Imager (MUVI) aims to monitor Earth’s ionosphere and report weather patterns to climate scientists within a 2U cube satellite footprint. The imaging equipment consists of a microchannel plate and phosphor screen that require 2.5kV and 5.5kV respectively at microamp level currents. This report explains the implementation of a high voltage boost cascaded flyback converter to meet all of the MUVI satellite output voltage requirements. …

Development Of A Portable Low-Moisture Food Pasteurization Device Using Rf Heating, Eric Jason Ohata

Master's Theses

Bacterial presence in low-moisture foods such as flour, cereals, baby formula, and spices, have become a concern due to sanitizing challenges. The food industry currently focuses on wet food sanitation as opposed to low-moisture foods because of bacteria’s inability to reproduce in low water activity media. Traditionally, food processing RF heating pasteurizes in mass quantities while an equivalent consumer device does not exist the market today. A consumer product would help eliminate food waste by providing an easy way to sanitize food and extend shelf life. The Portable Food Pasteurization (PFP) project is an interdisciplinary project involving the Electrical Engineering, …

Direct Drive Solar Panel Control Circuit, Marcorios Bekheit

Physics

A control circuit is built for insulated solar electric cookers (ISEC). Power delivery and temperature safety are the focus. Using a maximum power point tracking (MPPT) algorithm, Arduino Nano, voltage and current sensors, and a buck converter, the solar panel’s output power was maximized for a direct load heat resistor with 3.5Ω for a range of solar intensities. Using a resistance temperature detector, a temperature sensor is built for safety shutoff.

Neural Network For Monitoring Infant Feeding Process In The Smartbottle Device, Jiajun Guan

Master's Theses

To research the relationship between Childhood obesity and infant feeding patterns, the Electrical Engineering Department at California Polytechnic State University has designed a SmartBottle device attaching to the bottom of a baby bottle to monitor the infant feeding process. This project mainly focuses on the software and firmware design, as well as the neural network design of the SmartBottle device. The SmartBottle device is designed to identify infant feeding activities and to record related data for overweight and obesity research on children. This device includes a 6-dimensional inertial sensor that contains a 3-axis digital accelerometer and a 3-axis digital gyroscope. …

Design Of An Ultra-Wideband Frequency-Modulated Continuous Wave Short Range Radar System For Extending Independent Living, Toai-Chi Nguyen

Master's Theses

Falls in the disabled and elderly people have been a cause of concern as they can be immobilized by the fall and have no way to contact others and seek assistance. The proposed frequency modulated continuous wave (FMCW) short range radar (SRR) system, which uses ultra-wideband (UWB) signals can provide immediate assistance by monitoring and detecting fall events. The unique characteristics of this system allow for a frequency-based modulation system to carry out triangulation and sense the location of the fall through the usage of a continuous chirp signal that linearly sweeps frequency. This project focuses on the development, design …

Controller Modeling And Stability Analysis Of Multiple Input Single Output Dc-Dc Converter, Astha Adhikari

Master's Theses

This thesis entails the stability analysis of the Multiple Input Single Output (MISO) DC-DC converter developed for the DC House Project at Cal Poly. A frequency domain control system model of the MISO converter was designed and constructed using MATLAB Simulink. Transfer functions were derived and modeled for each stage of the converter to best fit the converter circuit system used in the original MISO circuit. Stability metrics such as overshoot, undershoot, rise time, phase margin and gain margin were measured to evaluate and analyze the stability of the converter. These metrics were measured with the original model including the …

Early Wildfire Detection With Line Sensors, Virginia Yan

Master's Theses

Over the last few years, wildfires have become more devastating to communities as the fires are inevitably destructive to many homes, businesses, and ecosystems. Frequent wildfires also pose a significant threat to power grids and nearby residents as they can damage transmission lines and other electrical equipment, which in turn can cause major power shutdowns. Especially in western U.S., severe drought conditions and weather variability cause residents to become more vulnerable to wildfire disasters as their safety is threatened. We are incompetent to control the wildfires effectively despite existing advanced technologies. Hence, an algorithm based on energy conservation and heat …

Programmable Battery Management System, Jason Erbert

Electrical Engineering

Lithium batteries provide excellent energy storage capabilities at a relatively high density; however, precautions must be taken with these high energy devices to ensure safe operation. A battery management system (BMS) provides protection by monitoring cell and pack voltage levels and maintaining them in a specific range. They limit the output current and disable the output in extreme conditions. Most devices in the targeted power range (<1000W) do not allow the user to manipulate the values for maximum current, cut-off voltage, or other limits. This project introduces the Programmable BMS (PBMS), which instead allows the user to select these values through a physical interface. The interface displays measurements including pack voltage and output current, and it reports additional characteristics of interest such as the battery’s temperature, state of charge, and cumulative number of charge cycles. This level of access and control permits users to receive the maximum performance and safety from common lithium battery packs.

Smart Motor Syringe System, Conard Chan, Jenny Chiao

Electrical Engineering

Syringe pumps are widely used in many research applications especially in the applications that need precise control. Today most medical research utilizes syringes to control the fluid being pumped to the experiment objects. In most cases microscopic or nano-scopic motion control is required to acquire optimal results, such application includes purification of DNA/RNA from contaminants[1]. The high precision required to control the syringe pump makes it difficult to perform manually. This paper focuses on the design of an intelligent syringe pump motor control system to achieve reliable and precise control for biomedical experiments. This project improves medical research quality with …

Iot Camera System For Monitoring Strawberry Fields, Simon Schoennauer

Master's Theses

A wireless imaging system for monitoring strawberry fields provides enough quality image data for computer vision algorithms to make meaningful yield predictions. This report contains a design for a wireless sensor network modified with mesh networking techniques to extend coverage range and a solar energy harvesting system to improve sensor node lifetime. A two hop system with six nodes is implemented in a laboratory environment validating the communication systems integrity over an 800’ range. Moving from a primary battery system to solar energy harvesting increases the module lifetime indefinitely.

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

Iot Asset Tracker, Jonny M. Erickson, Matt A. Murray

Electrical Engineering

This senior project will be the completion of an IoT asset Tracker. In today’s day and age, technology is weaving its way into every aspect of life. Because of this, we demand to know more and more information about everything that is going on in our lives. One of these needed pieces of information is knowing the location of our most valuable assets. This is the main goal of this project: to build a portable SMS driven GNSS tracking device. The device is designed to provide two methods of tracking for any mobile asset. The device will utilize a large …

Distance Estimation Using Ofdm Signals For Ultrasonic Positioning, Kyman Huang

Master's Theses

This paper describes a method of estimating distance via Time-of-Flight (TOF) measurement using ultrasonic Orthogonal Frequency Division Multiplexing (OFDM) signals. Using OFDM signals allows the signals and their sub-carriers to remain orthogonal to each other while continuously transmitting. This estimation method is based on the change of phase of a traveling wave as it propagates through a medium (air for ultrasonic signals). By using signals containing multiple tones, the phase change between each frequency component is slightly different. This phase difference is dependent on the distance traveled and can thus be used to estimate distance. This paper studies the impact …

The Design, Testing, And Analysis Of A Constant Jammer For The Bluetooth Low Energy (Ble) Wireless Communication Protocol, Aiku Shintani

Master's Theses

The decreasing cost of web-enabled smart devices utilizing embedded processors, sensors, and wireless communication hardware have created an optimal ecosystem for the Internet of Things (IoT). IEEE802.15.4, IEEE802.11ah, WirelessHART, ZigBee Smart Energy, Bluetooth (BT), and Bluetooth Low Energy (BLE) are amongst the most commonly used wireless standards for IoT systems. Each of these standards has tradeoffs concerning power consumption, range of communication, network formation, security, reliability, and ease of implementation. The most widely used standards for IoT are Bluetooth, BLE, and Zigbee. This paper discusses the vulnerabilities in the implementation of the PHY and link layers of BLE. The link …

Rf Power Amplifier, Angel De Jesus Delgado, Rachanon Wajanakunakorn, Andrew John Ferguson

Electrical Engineering

Wireless devices are part of everyday life, cellphones and radio receivers impact more people than any piece of technology. Thus, the respective building blocks continue to advance and achieve better performance. A primary component of all wireless communication systems is the power amplifier that drives the antenna. The Institute of Electrical and Electronics Engineers (IEEE) holds the International Microwave Symposium (IMS) every year where teams compete internationally for the most efficient RF Power Amplifier (PA). Power amplifier technologies strive to maximize efficiency and linearity. Topologies to consider are D, E, F, F-1 and Doherty since they have a maximum theoretical …