Electrical and Electronics Commons^™

Design Of High Efficiency Doherty Power Amplifier, Kobi G. Kelly, Severin Pindell

Electrical Engineering

The project includes design and fabrication of a high efficiency power amplifier for a student design competition held at International Microwave Symposium (IMS) 2023. Efficient power amplifiers are critical for base station communication requiring efficient use of available power. The final design optimizes power added efficiency (PAE) and linearity. The amplifier will operate at 2.45 GHz. Competitive PAE above 50%, and C/I above 30 dB is achieved by leveraging a Doherty class amplifier using accurate discrete CGH4006P transistor models to simulate an efficient and linear design. Unique design features include optimal transistor bias point selection and power split ratios between …

Formula Sae Vehicle Dynamics Controller, Luke Edward Bosworth

Electrical Engineering

Throughout the history of motorsports, engineers have continuously pushed the boundaries of speed and control in the pursuit of enhancing vehicle performance on the track. Today’s top performing motor-vehicles leverage electric motors to the deliver instantaneous torque to the vehicle’s tires. While these electric motors can deliver a lot of power very efficiently, the delivery must be well controlled to get the most performance out of the tires. The Formula SAE Vehicle Dynamics Controller (VDC) senior project integrates vehicle modeling, state estimation, and yaw moment controls into a small- scale Formula-one style electric vehicle, improving vehicle performance and laying the …

2024 Marine Energy Collegiate Competition, Nora Riedinger, Miles Mikkelsen, Brendan Stratford, Derek Tom, Zach Kwast, Harmon Yanikian-Sutton, Kennedy Urcelay, Tori Thomas, Brady Caron

Mechanical Engineering

PolyWave Energy is the second team from California Polytechnic University at San Luis Obispo to compete in the Marine Energy Collegiate Competition. PolyWave Energy consists of Mechanical Engineering, Electrical Engineering, and Business Administration students who have worked together from September 2023 to May 2024 on designing, building, and testing a marine power device to serve a selected market.

In response to the escalating concerns surrounding carbon emissions, climate change, and the depletion of fossil fuels, California Polytechnic State University’s Polywave Energy team has developed a sustainable and reliable energy source for Autonomous Underwater Vehicle (AUV) charging. Through extensive research of …

Design And Analysis Of A New Buck-Boost Converter With A Low-Side Switch, Abdullah Awidah

Master's Theses

This work explores the design, simulation, construction, and analysis of a novel Non-isolated DC-DC Buck-Boost converter which has the advantage of incorporating a low-side switch compared to the traditional buck-boost which requires a high-side switch. This allows the use of a low-side driver which further simplifies the design and operation of the converter. The proposed Buck-Boost converter was constructed to provide -24 V output from an input range of 12V-18V with 15V nominal input at 10W maximum output power utilizing 500kHz switching frequency. Findings from simulations and hardware tests verify that the converter effectively provides the desired -24 V output …

An Analysis Of Indoor Air Quality At Cal Poly For Sensor Design, Isabella M. Santi

Master's Theses

Prior research has shown that indoor air quality (IAQ) impacts cognitive performance. At Cal Poly, many older buildings are unable to maintain appropriate IAQ because of their outdated ventilation systems and the increasing number of students in the rooms. This work analyzes the IAQ of different buildings at Cal Poly, with a focus on Building 20. Carbon dioxide, temperature, and relative humidity inside classrooms are collected using an integrated circuit sensor and a microcontroller. A total of 38 hours of data was collected, with 22 of those hours in Building 20 specifically. We find that unlike temperature and relative humidity, …

A Hybrid Computer To Solve The Selective Harmonic Minimization Problem In Single-Phase Inverters, Dillon Nguyen

Master's Theses

Power electronics possess forms of non-ideality due to the nonlinearity present in physical switches. These switches are driven with pulse width modulation (PWM), which properly down-converts or up-converts based on converter topology. When these switches turn on or off, they introduce the main proponent of efficiency loss: harmonics. This becomes a nonlinear optimization problem with many converters. The solution proposed in this thesis is an analog/digital hybrid computer that utilizes the speed of analog computation and the accuracy of digital computing together. A Plexim RT Box provides the programmability needed for algorithms, while the analog circuit provides low-power, high-speed computation …

Design Of A Dynamic, Reconfigurable, Self-Balancing Battery Pack, Alexander Hallett Neiman

Master's Theses

This thesis details the design and testing of a reconfigurable battery array. Reconfigurable battery arrays, specifically for mobile applications, have the potential to reduce or eliminate use of auxiliary charging, balancing, and inverter systems. Design work included a bidirectional solid state switch and a cell-to-cell bidirectional current-limiting power converter. While the overall efficiency, size, and cost of the battery pack was not competitive with existing options, it demonstrated cell-to-cell balancing and native four-level square wave AC inverter output with an array of only two cells. This demonstrates viability of the concept as well as reveals important requirements and safety features …

2-Channel Eeg Neurofeedback System, Tim Erwin, Donna Nikjou, Sebastian Turkewitz

Electrical Engineering

This work describes the design of an EEG-based neurofeedback system which provides users with real-time feedback on their level of focus or relaxation. By analyzing the spectral content of the brain activity measured via scalp electrodes, focus and relaxation levels can be quantified. Based on these measurements, live feedback in the form of moving bar graphs is provided to users, allowing them to gain awareness of their mental-state and more efficiently learn how to consciously relax or focus. This project covers the design of the system, including amplification and filtering stages, digitization, and signal processing. The system interfaces with a …

Design And Characterization Of A Broadband Rf Switch Utilizing Surface Mount Devices, Daniel Bracamontes

Master's Theses

High frequency solid-state switches are critical elements in communication systems, radio frequency (RF) systems and instrumentation. Key parameters to an RF switch include insertion loss while on and off-state isolation. Power handling and linearity are important to consider for a cost-effective construction. This becomes a design challenge into K-band frequencies as components required need to be small, dielectric losses and transmission lines need to be physically matched for proper isolative and through states. This thesis presents a novel single pole eight throw (SP8T) hybrid design composed of commercially available surface mount technology solutions to achieve high isolation and low insertion …

Design And Analysis Of Zero Voltage Switching Hybrid Voltage Divider, Stephen Ulysses Alvarado Estrada

Master's Theses

This work explores the design, construction, and analysis of a novel DC-DC converter which incorporates combinations of switching capacitors and inductors to achieve an integer voltage divider function, without the need for a feedback loop controller to achieve the desired output voltage. The proposed Hybrid Voltage Divider additionally provides zero voltage switching (ZVS) at turn on transitions which yields improved overall efficiency of the converter. Besides a proof-of-concept via computer simulations, another primary goal of this thesis is to demonstrate the functionalities of the proposed Zero Voltage Switching Hybrid Voltage Divider (ZVS-HVD) through hardware prototyping. The proposed ZVS-HVD was designed …

Plc Course Development, Leonard Hernandez, Jacqueline Grace Radding

Electrical Engineering

The goal of this project is to design and construct the first lab experiment for the newly developed EE435 laboratory course. The experiment entails PLC programming to automate LED lighting in a simulated building. Starting with why PLCs are used, how to use the interface of EcoStruxure Control Expert V15.0 and practice using logic to control the dimming of a Light Emitting Diode (LED) to sustain a certain number of lumens consistent in a zone. Through the lab manual developed in this project, students will gain experience of creating logic designs using Function Block Diagram (FBD) and learn the layout …

Improvements Of Hybrid Ac/Dc House Prototype, Arden Abude

Electrical Engineering

This is an iteration from previous designs of the Hybrid AC/DC House with a systematic addition of a portable AC power supply unit. This iteration for the Hybrid AC/DC House is an innovation of independence for sustainable housing solutions. It will serve as an alternative for rural communities needing power to rely on self-sustainable microgrids rather than large-scale AC electric grids. The addition of a portable AC power supply would allow the microgrid to remove its reliance on AC power from the larger grid and would elevate the system to complete energy independence. The microgrid has DC power generated from …

Hybrid Wall Outlet For Ac Or Dc Power Delivery, Garrett Knoller, Kerr Allan, Greg Perini

Electrical Engineering

The goal of this project is to develop hybrid DC and AC wall outlets for an efficient, flexible power interface. A DC plug standard is also proposed to allow DC devices to be safely powered by the outlet with the correct DC voltage for each device. The primary objective is to create a power outlet compatible with the proposed DC plug as well as NEMA 5-15 AC plugs, enabling the same outlet to power both types of load as needed. The outlet is intended for buildings and systems transitioning to an isolated DC grid to encourage DC development and adoption. …

4-Band Personal Eq Device, Carson Kellerman

Electrical Engineering

The device is a 4-band EQ with 3.5mm audio input and output jacks. The device has 4 adjustable EQ bands. Each of the 4 bands are adjustable via knob potentiometers, and are able to boost or cut their respective center frequencies of 150Hz, 400Hz, 2500Hz, and 10kHz from -15dB to +15dB. The device is battery powered off of 1 9V battery and is able to function for 10 hours before needing to replace the batteries. The device has a Total Harmonic Distortion of less than 1% and a Signal to Noise Ratio greater than 60dB. Overall, this device allows music …

Electronic Note-String Detector, Gavin Garcia-Rossi, Tommy Smail

Electrical Engineering

As the virtual space has become a dominant part of everyone’s day-to-day lives, many normal face-to-face interactions and services have not yet been facilitated by adapting technology. One of these prevailing areas is music lessons. Over Zoom meetings, or other virtual platforms, it is tremendously challenging to teach students. These challenges include recognizing student mistakes audibly and visually, and being able to give confident feedback on the incorrect notes played by learning musicians. Without having to delve into improving the complex systems that would be required to improve audio, video, and connection quality of these connections, we have another solution …

Hvac Fan Cooling System Using Modicon M580, Ogbonnaya Okoronkwo Okorie, Nicolas Jens Fache

Electrical Engineering

A common problem that many devices have when operating is overheating. Whether it is operating at full capacity or idle, those devices that we use exert heat to some type of extent. The physical and electronic components of the device can only withstand so much heat before the component becomes damaged. This product provides a method of preventing overheating by being a cooling system for your device. A solution for preventing overheating of the components in these electronic devices is by having some sort of cooling system. Our product’s cooling system will be based on energy efficiency, which means that …

Directional Speaker, Gabriel Tramontina Ceribelli, Vincent Trevor Pierce

Electrical Engineering

Parametric Acoustic Arrays (PAA) are highly directional soundwaves whose attenuation and spread are much less affected by distance from the source as compared to traditional speakers. A well-known application for PAA is the directional speaker. Studies show that noise directly affects health and decreasing noise pollution can help improve the quality of life for millions of people. Directional speakers can revolutionize society by coupling space with sound. This project encodes audio into two RF-Pulse Width Modulated (PWM) waves to drive a transducer array. Each RF-PWM wave interferes with the other in air to generate a Single Sideband (SSB) frequency spectrum …

Multi-Effects Analog Guitar Pedal, Carson J. Bryan

Electrical Engineering

The Multi-FX Analog Guitar Pedal includes the analysis, design, performance, PCB layout, and packaging of an industry-standard effects pedal for an electric guitar. This project takes an analog input signal and utilizes analog circuitry to give the user the option to customize the way that their playing sounds. Effects include the options to add equalization filtering and distortion. The EQ filtering will allow the user to attenuate or gain certain frequencies divided into the 3 standard audio bands: bass (20-300 Hz), middle (300-4000 Hz), and treble (4-20 kHz). The soft-clipping distortion stage will allow the user to move around the …

Efficiency Study Of A Hybrid Ac/Dc House, Eunice Dominique Solomon Santiago

Master's Theses

With the proliferation of residential-scale renewable energy sources and DC loads, it has become attractive to use residential DC electrical system that could offer benefits over the legacy residential AC electrical system. The Hybrid AC/DC house provides a sustainable alternative to preexisting residential electrical system by having both AC and DC buses. The DC bus facilitates the connection from DC sources to DC loads, whereas the AC bus interfaces AC sources to AC loads. The study develops the equations to calculate losses based on a model consisting of four main components: Multiple-Input Single-Output (MISO) converter, AC-DC converter, inverter, and DC-DC …

Design Of Class F-Based Doherty Power Amplifier For S-Band Applications, Kyle Chang

Master's Theses

Modern RF and millimeter-wave communication links call for high-efficiency front end systems with high output power and high linearity to meet minimum transmission requirements. Advanced modulation techniques, such as orthogonal frequency-division multiplexing (OFDM) require a large power amplifier (PA) dynamic range due to the high peak-to-average power ratio (PAPR). This thesis provides the analysis, design, and experimental verification of a high-efficiency, high-linearity S-band Doherty power amplifier (DPA) based on the Class F PA. Traditional Class F PAs use harmonically tuned output matching networks to obtain up to 88.4% power-added efficiency (PAE) theoretically, however the amplifier experiences poor linearity performance due …

Cubicom: Noisy Office Environment Communication Device, Nicholas Alan Maley, Joshua Michael Heeren, Alejandro Peña

Electrical Engineering

The CubiCom is a system that enables secure and clear communication between users in a noisy office space. It can function in any small cubicle within a 12 foot radius. The system consists of a series of wireless headsets for 6 users to transmit and receive audio, and a communication box that facilitates this process. These headsets are noise-dampening, preventing ambient sounds from interrupting conversation and making sure that all parties can hear each other clearly. Line-of-sight (L.O.S.) with each headset is required to have proper communication between users. This feature ensures no one outside of the room can eavesdrop, …

Analog Circuits For Computing, Nicole Christine Pickett, Lauren Cathy Sueko Chun, Dillon Ryan Nguyen

Electrical Engineering

This project entails designing, simulating, and verifying analog circuits that can perform essential computing functions for power systems applications. The project aims to remedy critical challenges associated with handling calculations digitally, namely, time and power. This project's scope includes creating a library of circuits in SPICE that can be used to model and simulate complex mathematical equations. From these SPICE models, the circuit can be constructed physically, where the solution can be generated in less time using less power than doing the computation digitally. The performance and efficiency of analog computing will be measured and compared to conventional digital methods.

Low-Cost Portable Laser Communication Device, Tom Elkayam, Basile Louis Scoffie

Electrical Engineering

The portable laser communication device (PLCD), is a low cost system used to set up networks in data isolated regions via an optical line-of-sight communications protocol. In this manner the PLCD transmits at 9600 baud using UART protocol over the visible light band at 635nm. The device is intended to operate in indoor conditions and be semi-permanent until redeployed. The PLCD is built as a transmitter, receiver pair and when installed, utilizes tracking to find each other and automatically set up communication within a window of 30° laterally and 10° vertically. Each side of the system is less than 15 …

Vr Force Feedback Gloves, Mark Wu, Claire Chen

Electrical Engineering

The goal of this project is to produce a manufacturing plan for a consumer VR glove. The total addressable market of VR is over 170 million global users as of 2022 (Kolmar , 2022) with a serviceable available market of 300,000 users on Meta’s own social platform (Heath, 2022). The targeted Quest 2 platform utilizes handheld controllers, which causes a lack of immersivity in social settings and gaming scenarios. One common use of the platform involves social platforms such as “Horizons” where users meet in a virtual world to interact; handheld controllers don’t allow users to shake hands, make finger …

Instrumented Control Column For Optionally Piloted Aircraft, Andrew J. Klein

Electrical Engineering

Natilus, an aerospace company that is rapid-prototyping optionally piloted aircraft (OPA) for the shipping industry, needs a system that retrieves control column position data in order to manipulate flight simulator parameters in software. At present, a universally compatible system for all aircraft does not exist. Typically, established aerospace companies will sink significant time and money into developing proprietary systems for control column data retrieval as every aircraft is unique in its layout and linkage design. However, as a startup developing their first aircraft, Natilus does not have the privilege of modifying an existing sensor system to work with their HIL …

Cardio Trainer, Levi Rash, Cristian Rodriguez

Electrical Engineering

The Cardio Trainer Device is a wearable device that guides the user through a physical exercise based on the user’s heartbeat measurements. Users interface with the device via a wearable band. The band determines the heartbeat of the user in real time and, using that reading, gives the user verbal instructions to optimize their workout. These verbal instructions then serve to control the physical exertion of the user and are delivered through an audio device. Users input personal physical metrics to the Cardio Trainer Device that tailor the performance of the device in a manner of ways: rate of instruction, …

The Design And Construction Of A Radio Telescope, Avery Elizabeth Bunting, Kira Hope Tolman

Architectural Engineering

Two architectural engineering students and an electrical engineering student worked together to design and build a radio telescope that is capable of using hydrogen line astronomy to map the galaxy. The telescope is made entirely out of aluminum, which, combined with small deflection limits, made for an iterative design process that focused primarily on constructability and supporting the desired outcomes of the electrical side.

Programmable Vibration Table Retrofit With Eagle Medical, Jonathan Ilagan, Madhav Asok, Max Lewter

Biomedical Engineering

This project aimed to repair and upgrade a vibration table used for package testing for the sponsor, Eagle Medical - a medical packaging and sterilization company based in Paso Robles, California. The current vibration table is not programmable and lacks circuit diagrams, making it difficult to repair. In addition, it is not functional due to internal circuitry issues and power requirements. To address these issues, the team will implement several upgrades to improve the product and allow for better random cyclic vibration testing. A full assessment of the existing vibration table will be conducted to ensure the viability of these …

Diy Cell Incubator, Hayden James Jeanor

Electrical Engineering

The purpose of creating a cell Incubator is for the development of cell and tissue production in laboratory settings. Large scale research projects and the medical community grow cells for various reasons, including experiments and creating tissue for patients. However, they cannot simply depend on growing cells in a petri dish that sit on a rack at room temperature. To grow heathy cells in the fastest way possible, they use cell incubators. Cell incubators create an atmosphere within the incubation bay that is designed to promote cell growth. The three main components that need to be constantly regulated, using a …

Hypoxic Incubation Chamber, Simone Lisette Helfrich, Makenzie Nicole Jones

Biomedical Engineering: Graduate Reports and Projects

This paper describes the design, manufacturing, and testing of a novel controllable hypoxic incubator with fully functional oxygen gas control and temperature control in a humid environment. On the current market, a majority of the few hypoxic incubators use pre-mixed gas that does not offer precise control over gas concentration. The objective for this project was to create a chamber that allows the user to set the O2 concentration to varying set points of % O2 while maintaining the chamber at a constant body temperature, CO2 level, humidity, and sterility. To start the project, multiple concepts were developed for the …