Engineering Commons^™

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. …

Skip The Grid: Restoring Light To The Navajo Nation, Diego Isaias Gonzalez

Construction Management

Skip the Grid is an interdisciplinary service project through California Polytechnic State University, San Luis Obispo (Cal Poly) where students and faculty partnered with sponsors including SOLV Energy and Goal Zero, and facilitation by Heart of America, an educational equity non-profit, to bring solar power to 27 families of school aged children in the Navajo Nation. The Navajo Nation is a historically disadvantaged community which lacks the infrastructure and financial capacity to provide electrical service to about a third of the families living on the reservation. Families in the Red Mesa and Chinle School Districts were the focus for this …

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …

Installation Of Electrical System For Paso Robles Police Department, Peter D. Strykers, Jacob M. Studebaker

Construction Management

This paper outlines the process that Peter Strykers and Jacob Studebaker went through to set up the lighting and power system for the Paso Robles Police Department gun range located off highway 46. Before our installation, the gun range had zero lighting so the officers could not use it after sunset. We allowed the officers to light the gun range with outdoor LED lights, light up both the storage units on site, and have access to multiple outlets inside and out of the storage units. The power source that the electrical system runs on comes from a Kubota generator because …

Sustainable Energy Storage, Jacob S. Grillo, Alyse C. Coonce, Jack R. Linchey, Nick P. Schnorr

Mechanical Engineering

This Final Design Review document covers the work we, students at California Polytechnic State University – San Luis Obispo, have performed in collaboration with Mr. Harish Bhutani and Dr. Mohammad Noori. The project’s intent is to create an energy storage system for off-grid and developing region applications using alternative technologies to lithium-ion battery storage. We plan to manufacture and assemble a scale model of the energy storage system to prove effectiveness and practicality. This system will store enough energy to power basic appliances and essential devices for a house or community. The chosen design direction will be a flywheel, as …

Adapted Tricycle 2021, Carolyn Graven, Daniel Coleman, Sebin Cho, Farhan Khan

Mechanical Engineering

This document describes and outlines the details of the senior project completed by a team of four mechanical engineering students in their final year at California Polytechnic State University, San Luis Obispo. The team worked with Linda Wolff at California Children’s Services to reach their main goal: to create an exercise tricycle that can be used by Savannah. Savannah is a young adult, and she needs to be able to steer, brake, and power the tricycle using almost entirely her core muscles. Over the course of the project, the team worked to design and build a safe and functional tricycle …

Solar Photovoltaic Iv Curve Tracer, Jonathan W. Skelly

Electrical Engineering

The Solar Photovoltaic Current-Voltage (IV) Curve Tracer, sponsored by Cal Poly Professor Dale Dolan, characterizes solar array current vs. voltage curves for any given temperature and irradiance. The curve tracer is battery powered, and functions autonomously across loading conditions from short circuit to open load on any sub-450-watt solar array. The curve tracer supports separate data logging modes for both single cells and single modules to maximize data accuracy for each. For testing full strings of solar panels, up to 10 IV curves may be stored in persistent EEPROM memory. Stored data may be recalled later for output to a …

Fitness Plug, Evan Lee Ashley

Computer Engineering

My parents only allowed me to play videogames or watch television for a certain number of minutes or hours per day. By limiting screen time, they encouraged me to be active and find other things to do outside of television or videogames. The Fitness Plug aims to do both by converting time exercised to entertainment time; you can only watch television or play videogames for as long as you have exercised.

Distribution Line Multi-Tool, Michael Andrew Garcia, Drew Miller, Sukhdeep Singh, Ritwik Kesavath

Electrical Engineering

Power companies are always interested in the best possible monitoring equipment for their grid. The power line multi-tool developed would aid in the monitoring of the power system’s distribution network. This device assesses the current conditions of distribution power lines. The device is able to measure current, detect downed power lines, as well as recognize fire starting conditions, and have wireless communication for ease of access and installation. Overall this device greatly aids in helping utilities monitor their grid in more detail.

With the increase of dry climates yearly, several utility companies are taking measures to aid in the prevention …

Lawn Buddy, Jayson Johnston, Andrew Brown, Jacob Maljian

Electrical Engineering

Grass lawns are a common hallmark of the American home. In 2019, a survey from the National Association of Landscape Professionals found that 81% of all Americans owned a lawn [1]. Mowing is a time consuming and costly chore that is part of maintaining a grass lawn. The manual labor in mowing a lawn can exceed 40 hours per year [2]. People commonly incur weekly costs on mowing services to save time. Traditional gas powered mowers are physically demanding and use engines that need routine maintenance. They operate loudly enough that users should be wearing hearing protection and the noise …

Multiple Input Single Output Converter With Maximum Power Point Tracking For Renewable Energy Applications, Kenneth K. Nguyen, Taufik Taufik

Master's Theses

In this thesis, a maximum power point tracking (MPPT) for multiple input single output (MISO) converter is presented such that power generated from multiple individual energy sources can be combined to deliver the maximum amount of power to a common resistive load. Typically, MISO converters will employ techniques that yield equal current sharing from each energy source. However, this may not be desirable since each source may be rated at different power ratings and/or may experience different operating conditions, preventing the system MISO converter to acquire the most available total power from the sources. Utilizing MPPT control would therefore be …

Dc To Dc Usb-C Charger, Nikki Gmerek, Kenneth Nguyen, Uriel Serna

Electrical Engineering

The DC House USB-C Charger will convert the 48V input from the DC house, found on the Cal Poly campus, to 3 USB-C outputs: 5V, 12V, and 24 volts. The converter will deliver a total of 185 Watts out across all 3 outputs, with an efficiency greater than 82% at full load. The USB-C ports will be used to connect to compatible phones, laptops or any other device for charging/powering purposes. The goal of this project is to develop the most efficient and safe converter to deliver power to multiple outputs using USB-C, for items as small as a cell …

Cal Poly Ee 518 Electric Power Protection Laboratory, Richard Terre, Vincent Tham, Austin Kurth

Electrical Engineering

Facing a rapidly-changing power industry, the electrical engineering department at Cal Poly San Luis Obispo proposed Advanced Power Systems Initiatives to better prepare its students for entering the power industry. These initiatives call for the creation of a new laboratory curriculum that utilizes microprocessor-based relays to reinforce the fundamental concepts of power system protection.

The electric power protection laboratory (EPPL) senior project is the validation of lab manuals written for the planned EE-518 power system protections laboratory looking to be offered in Spring 2020 alongside the current lecture class under the same designation. This report evaluates the lab manual, verifies …

Usb-C Power Adapter For Dc House Project, Tyler G. Starr, Ezzeddeen Gazali

Electrical Engineering

Despite the importance of electricity and the impact it has on our daily lives, many people around the world still live without this essential utility today. According to the International Energy Agency (IEA), approximately 1.1 billion people in the world did not have access to electricity in 2017. The DC House Project at Cal Poly aims to provide electricity to people living in rural areas by directly utilizing DC energy generated from renewable or human powered sources without the need for DC-AC conversions. However, one significant issue is the lack of a standardized DC wall socket. Standards for AC wall …

Daily And Seasonal Variability Of Offshore Wind Power On The Central California Coast And Statewide Demand, Matthew Douglas Kehrli

Physics

No abstract provided.

Grid-Tied Solar System, Virginia Yan

Electrical Engineering

Distribution level solar energy generation has gained importance and popularity, because it helps create a sustainable electricity system while reducing the harmful environmental impacts our current power systems have. This project proposes an alternative energy source, a laboratory-scale grid-connected photovoltaic system. A KC120-1 solar panel produces 120 Watts maximum. A grid-tied solar power inverter does DC-to-AC conversion and minimizes energy transfer losses. The inverter also has an anti-islanding feature, which senses a power outage and prevents back-feeding through isolating the circuit. The circuit breakers isolate electrical components and protect the circuit. Schweitzer Engineering Laboratories SEL-751 feeder protection relay and SEL-735 …

Logging, Visualization, And Analysis Of Network And Power Data Of Iot Devices, Neal Huynh Nguyen

Master's Theses

There are approximately 23.14 billion IoT(Internet of Things) devices currently in use worldwide. This number is projected to grow to over 75 billion by 2025. Despite their ubiquity little is known about the security and privacy implications of IoT devices. Several large-scale attacks against IoT devices have already been recorded.

To help address this knowledge gap, we have collected a year’s worth of network traffic and power data from 16 common IoT devices. From this data, we show that we can identify different smart speakers, like the Echo Dot, from analyzing one minute of power data on a shared power …

Microgrid Protection Student Laboratory: Human-Machine Interface And Scada Database, Nathan P. Martinez

Electrical Engineering

The electric utility system, a ubiquitous and fundamental component of modern life, has changed more in the last 20 years than the last 100. With more homes and businesses installing distributed energy resources (DERs) such as solar panels, battery storage, and other intermittent sources, massive changes need to take place in the electric transmission and distribution systems. Engineers must develop a new skill set for a modern utility industry. This project summarizes a component for a new laboratory class aimed at power engineering students at Cal Poly which supports the laboratory through the creation of a human-machine interface (HMI) and …

The Modified-Multiphase Boost Converter: Combined Inductors And Capacitors Topology, Zachary L. Eldredge

Master's Theses

In this work, a modified boost converter design has been implemented in a multiphase configuration with a condensed topology. The modified aspect of the design has already been proven to drastically reduce input current ripple by about 40% in a single-phase implementation. By placing two modified boost converters in parallel with interleaving main switches (multiphase), the input inductors and modified capacitors of the modified topology can be reduced to just one of each, lowering the number of components, size, and cost. Additionally, multiphase DC/DC converters lower input/output voltage and current ripples while delivering more power compared to single-phase converters. By …

Dc-To-Dc Buck Converter, Kyle Christopher Roman

Electrical Engineering

The growth of sustainable energy requires many components to work in harmony creating one efficient and effective system. Sustainable energy generation that produces a DC current varying in voltage requires a subsystem to convert voltage to a practical and usable value. The DC to DC Buck converter converts high DC solar generated voltage to a 12V output. This Modular -Level power electronic (MLPE) device performs as a solar charge controller for small lithium ion batteries. Fluctuating voltage levels generated by Photovoltaic cells makes the solar controller a critical part of the solar system. Regulating the DC voltage allows safe and …

Lab-Scale Circuit Breaker Module For Power System Laboratories, Amanda Barley, Allen C. Scozzari, Joshua E. Chung

Electrical Engineering

In this project, a circuit breaker that can simulate different types of power system faults is redesigned, constructed, and tested. They will then be implemented in power systems laboratory courses at Cal Poly. The project’s goal is to improve a previous circuit breaker design to help students better visualize how faults affect power systems in the real world. Two main improvements are made to the previous circuit breaker design. The first improvement is to power the breaker with a typical wall outlet adapter instead of the DC source from the Cal Poly power systems laboratory test benches. This lets the …

Hybrid Water Pump, Dylan W. Grant, Wei Chen Yeh

Electrical Engineering

This project seeks to use multiple sources to power a water pump. We will design a system which will combine inputs from solar and wind energy production to ensure the pump will have enough power to run. This will create a system powered by clean energy and will be self-sustained once completed. This will theoretically create a more sustainable source of power for the pump than only one of the sources. Because the power sources don’t require outside inputs (aside from sun and wind), the pump can be placed in a remote area. This could be very helpful in developing …

Dc House Energy Management System, Zachary L. Eldredge, Zoe M. Hay

Electrical Engineering

In this work, a previously completed proof of concept for an Energy Management System (EMS) for the DC House project has been revised and re-implemented. The implemented design changes will improve the performance and reproducibility of the system. This new design of the EMS replaces the two-separate buck and boost DC-DC converters with a single bidirectional DC-DC converter to reduce components and improve efficiency. Analysis of the bidirectional DC-DC converter shows high efficiency especially at larger load currents. The code of the previous work was updated for smoother operation as well as to accommodate an LCD capable of displaying more …

A Method For Evaluating Aircraft Electric Power System Sizing And Failure Resiliency, Cory Kenneth Kross

Master's Theses

With the More Electric Aircraft paradigm, commercial commuter aircraft are increasing the size and complexity of electrical power systems by increasing the number of electrical loads. With this increase in complexity comes a need to analyze electrical power systems using new tools. The Hybrid Power System Optimizer (HyPSO) developed by Airbus SAS is a simulator designed to analyze new aircraft power systems. This thesis project will first provide a method to assess the reliability of complex aircraft electrical power systems before and after failure and reconfiguration events. Next, an add-on to HyPSO is developed to integrate the previously developed reliability …

Power Distribution:Protection Analysis, Avneet S. Samra

Electrical Engineering

The objective of this project is to build a radial distribution system that operates on a lower voltage. The system consists of a transmission line protected by a SEL-351 Relay, a three- phase transformer protected by a SEL-587 Relay, and a three-phase induction motor protected by a Cooper Form 6 Controller. The SEL-351, SEL-587, and the Cooper Form 6 Controller are microprocessor-based relays that are used to provide protection under faulted conditions. When a fault is detected in the system, the closest upstream relay sends a trip signal to its assigned local breaker. The SEL-351 provides overcurrent protection for the …

Designing A Power Distribution System For The Arce 257 Revit Structural Model, Reid Wilhelm

Electrical Engineering

The construction industry needs engineers. Mechanical, electrical, and plumbing engineers, better known as MEPs, comprise a large number of employees who design and assist in the building of commercial structures. In particular, electrical engineers design power distribution systems for these buildings, including the power, lighting, low voltage, and fire protection subsystems.

Here at Cal Poly, architectural engineers enrolled in ARCE 257 create authentic structural plans for a fictitious two-story structure. This senior project transforms these structural plans into an architectural model and creates a power distribution system for the entire building. This is done through a building information modeling (BIM) …

Testing Feasibility Of Inductive Power Coupling For Modern Applications, Andrew Burman

BioResource and Agricultural Engineering

This project takes two bifilar tesla coils and uses them to find a % efficiency of power transfer as distances between the coils decrease. The reason this experiment is being conducted is to find possible implications for wireless charging of vehicles using similar style coils. This project conducted experiments on 60 Hz, 400 Hz, and 1 kHz frequencies for a small input signal. The general conclusion is that as the frequency increases more power can be transferred and higher efficiency of power transfer is seen. This project also concluded that it could be possible to get higher efficiency at a …

Integration Of Sel Relays To Provide Motor, Transmission Line, And Transformer Protection, Christopher Ewing, Bryce Keefer

Electrical Engineering

The objective of this project is to familiarize the performers with the principles of operation of the Schweitzer Engineering Laboratories (SEL) protective relays in both normal and fault conditions. The SEL-587, SEL-311L and SEL-710 microprocessor-based relays are used to provide protection for a system composed of transformers, simulated transmission lines and a 3-phase induction motor. Each of these relays provides protection by sending a trip signal to local breakers upon sensing a fault condition. The SEL-587 provides overcurrent and differential protection for a 3-phase transformer, while the SEL-311L provides differential and distance protection for a transmission line, and negative sequence. …

Rf Power Harvesting Rectenna, Jimmy Tang, Raymond Phu, Tom Geranios, Benjamin Muñoz

Electrical Engineering

Sustainability is one of today's primary engineering objectives. This principle involves system design that minimizes environmentally harmful energy emissions and resource consumption, and maximizes renewable energy practices [1]. Communication antennas transmit wireless signals that can be converted into usable energy. The Rectenna system described in this report, shown in Figure 1, was designed to accomplish this energy conversion, with -5dBm (316µW) minimum power at the rectifier input. Since typical ambient signal power is in the -70dBm (0.1nW) range, the proposed system could only convert passive, relatively high-power microwave band AC signals to DC. The Rectenna system was designed for 1.9GHz …

Solar-Powered Hot Tub, Jonathan Peterson, Anthony Zepeda

Electrical Engineering

This paper discusses the design and implementation of a solar-powered hot tub. The concept of this project was to design an independently-operated hot tub powered by a 12V rechargeable battery, charged during the day by a single 400W solar panel. For this purpose, a twenty-year-old name-brand hot tub was purchased, in used condition. The plumbing, AC electrical wiring, and mechanical pumps were all removed and replaced with new components to meet our design specifications. Additionally, a solar water-heater was designed and integrated into the system to directly apply the sun’s heat to water pumped in and out of the tub, …