Engineering 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 …

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. …

Dc To Ac Inverter For A Microgrid-Inspired Power Distribution Architecture For Electric Vehicles, Bryan A. Carrillo Martinez, Eli Blacklock, Paul A. Samson, William S. Holt-Hillis

Electrical Engineering

This project builds upon the prototyping of a microgrid-inspired power distribution architecture for electric vehicles (EVs). The efficacy of this prototype aims to inform a full-scale power distribution system that charges an EV battery, supports the electric grid with important ancillary services, performs peer-to-peer EV charging, and works in conjunction with other AC and DC sources and loads. The scope of this report focuses specifically on the design, construction, and testing of the DC/AC inverter. Future development of this distribution architecture will incorporate synchronous generators, a battery management system, and an Arduino/Raspberry Pi-based communication system to fully simulate an electric …

Development Of Cal Poly’S Hybrid Ac/Dc House, Eduardo Andres Muñoz, Giovanni Ramirez Angel

Electrical Engineering

The Hybrid House provides an example for what sustainable housing solutions could look like. It also functions as a potential solution to the current rural electrification issues many developing countries face. The use of a DC-DC MISO converter allows for combining multiple power sources into a single DC bus. The Hybrid House integrates the DC bus by employing the use of DC-DC converters for home use. This system may potentially improve the overall system efficiency by avoiding the losses associated with AC-DC converters. The use of the DC bus further leverages the Solar Panel renewable energy solution to become a …

Programmable And Modular Dc-Dc Converter, Joshua C. Hutchinson, Elijah M. Gordon

Electrical Engineering

This project considers the design, implementation, and testing of an open-source dc-dc converter for microgrid prototyping. Unlike conventional dc-dc converters that are proprietary and require specialist knowledge, and are usually designed for a single function, the proposed dc-dc converter will comprise of a programmable MCU and a Raspberry Pi (RPi) interface to allow less-skilled consumers to monitor and modify a power converting system. We will develop an open-source library that contains voltage control, current control, maximum power point tracking, and battery charge control profiles. Each library will be easy to implement through a GUI on the Raspberry Pi and will …

Development Of Multiple Input Single Output Dc-Dc Converter, Ryan Bailey, Miguel Carmona, Jose Velez-Lopez

Electrical Engineering

This senior project report details the testing and validation of the designed DC-DC Multiple Input Single Output converter. The MISO uses four-switch buck-boost topology to output a single 48V from multiple nominal 24V inputs. The previous iteration of the MISO was plagued with an overheating mosfet that would drastically reduce the lifespan of the boards and reduce efficiency. This newest iteration includes more ground panes to combat the issues. In addition, the 200W MISO board was redesigned to utilize an edge connector for secure installment, removal, and replacement in the actual DC House system panel. The slots also have a …

Tank Level Controller Plc Lab, Siddhi Upadhyaya, Teghvir Grewal

Electrical Engineering

The California Polytechnic State University San Luis Obispo’s Electrical Engineering Department is currently developing lab experiments for the new EE435 (Industrial Power Control and Automation) class. In order to support these efforts, fourth year Cal Poly students are expected to develop laboratory experiments that will be conducted during this new class for the semester system. The lab experiment focused on in this project is called the Tank Level Controller. This experiment will introduce EE 435 students to Schneider Electric Programmable Logic Controller (PLC) hardware and software, which is prominent in the automation industry.
This experiment will require students to develop …

Paired Storage Distributed Energy System Design For A Local Community Farm, Neil Albert Collison, Lily Goldman

Electrical Engineering

This project considers the design of a renewable energy microgrid for a 19-acre community farm in San Luis Obispo, CA as the farm seeks to increase the magnitude of its electrical loads, and gain back-up electrical capability. The microgrid design will enable lower carbon emissions, reduce demand on the utility grid while saving on energy costs, and provide improved reliability and resiliency to the operator of the community farm. The eventual implementation of the design by a professional engineering entity will allow the community farm to expand its education program to include renewable energy as well as gain notoriety in …

Current Source Dc-Dc Converter For Undersea Fiber Optic Sensors, Richard Anthony Esplana Kwan, John Charles Rodinec, Andrew Armstrong

Electrical Engineering

Today, there are nearly 400 cable networks spanning roughly 750,000 miles to connect our world together. With thousands of miles of cable already lying on the ocean floor, with thousands more to come, many have recognized a unique opportunity in using this cable infrastructure as an attachment point for sensors to help study and monitor the ocean. Placing sensors onto a submarine cable is not a simple task; the sensors will require power that they receive from a transmission cable, from a battery, or from the submarine cable itself. Unfortunately, the existing power feed configuration for submarine cables typically only …

Battery Hardware Simulator, Kian N. Orang, Marcelo Garcia

Electrical Engineering

This project aims to develop a battery hardware simulator, which will serve as a tool for studying microgrids. The primary objective is to create a simulation system that can emulate various battery technologies that are used in microgrids, including lithium-ion and lead acid. By utilizing this battery simulator, Cal Poly students can safely test battery management systems and battery-sensitive electronics without the inherent risks associated with real batteries. Our project implemented this design with a 4-quadrant programmable power supply (ITECH) connected to an AP Systems grid tied inverter. The power supply acts as the battery which can receive or supply …

Wireless Energy Harvesting System, Matthew Palma, Audrey Toop, Andrew Fahey

Electrical Engineering

The modern world is built upon wireless transmission of data. The signals that carry this data travel through the air, an untapped source of power. Unreceived transmissions are dissipated into useless forms of energy when they should be reclaimed. Wireless electronics can theoretically be powered by harvesting energy from the electromagnetic signals in the wireless internet frequency band. The aim of this project is to develop a system to capture ambient energy, convert it into DC power, and store the power for later use. The product will consist of three subsystems: an antenna receiver, a rectifier and voltage-multiplier, and a …

Power Thyristor Controller For Speed Control Of Dc Motor, Alejandra Zapata, Morgan Erich Boehme, Abdullah Mohammed Awidah, Payton Robert Chalstrom

Electrical Engineering

In this work, a Power Thyristor Controller for Speed Control of DC Motor has been developed with the purpose of replacing an existing simulation experiment, aiming to effectively implement the principle of learning by doing. The primary objective of the experiment setup is to illustrate the fundamental principles and operational mechanisms underlying the firing angle and controlled bridge rectifier. The new experiment is taking advantage of the existing FCRO4100 Single Phase Firing Board that was donated to the University by ENERPRO. The pre-programmed microcontroller is connected to the thyristor bridge rectifier that’s powered by 24VAC. Additionally, a DC motor will …

Battery Energy Storage System, Carlos Gonzalez, Philip Tafoya, Mariely Caraballo, William Hoang

Electrical Engineering

The Battery Energy Storage System (BESS) project consists of bringing an existing photovoltaic battery energy storage system into service within Cal Poly’s Energy Conversion Lab. Information regarding the BESS is limited to the existing manuals as the original equipment manufacturer has ceased supporting the product in the United States. Results from previous projects on the BESS speculated that a DC input may be required to enable the system’s to be fully operational. The goal of the project is to provide a DC input into BESS and test the system’s functionality. Initially, a Photovoltaic Thevenin Equivalent was expected to be utilized …

Smart Usb-C Wall Plug For The Dc House Project, Ridge Lahti, Dino Maslic

Electrical Engineering

DC operated devices and appliances powered by AC systems suffer inefficiencies resulting from the losses of converting AC energy into DC energy. At Cal Poly, the DC House Project aims to minimize the need for AC electricity in homes and encourage the use of renewable energy systems. The DC House uses a 48V DC bus that must be stepped down for use with increasing number of DC loads in a typical home. In this project, a Smart USB-C Wall Plug is designed to work with USB Power Delivery to provide a variable voltage output for use with these DC loads …

Controlling Temperature Of Dc-Dc Converter Using Switching Frequency Adjustment, Sajjad Ahsan, Arsalan Mughal, Mark Rapiz

Electrical Engineering

As DC-DC converter operates under different load conditions, the amount of loss within the converter varies accordingly. Consequently the temperature of the DC-DC converter will also change based on the load demand. For PWM based DC-DC converters, one factor that contributes to the loss; thus, the increase in temperature is the switching frequency at which the converter operates. The higher the switching frequency used, the bigger the switching loss and in turn the hotter the converter. In this project, the temperature of a DC-DC converter is controlled by changing the switching frequency used by the converter. The hardware investigation used …

Hybrid Ac/Dc Light Bulb, Celina Mendez, Kristian Vincent Cruz, Nouman Baryal

Electrical Engineering

A hybrid AC/DC house aims to maximize the use of AC electricity from the utility grid and DC electricity from renewable energy sources such as roof-top solar panels. The hybrid system will therefore improve the reliability of the electrical by enabling power to be delivered to the loads even when one of the sources is not operational. One of the critical loads that every house needs is lighting. The hybrid AC/DC system should therefore be reliably facilitating the power delivery to the lighting. In this project, a localized hybrid AC/DC for LED light bulbs is designed and constructed. The hybrid …

Hybrid Ac/Dc House: The Road To A Sustainable Future, Nicholas Mcadams, Luis Rodriguez

Electrical Engineering

The Hybrid AC/DC house is a sustainable alternative to preexisting residential power systems. The implementation of a DC bus in current homes will allow inefficient DC-AC and AC-DC conversions to be circumvented. This provides a direct path for current to flow to DC loads from DC sources such as solar panels to minimize power losses. In doing so, this will give users the ability to power their homes strictly from renewable sources and substantially decrease reliance on the utility. For this purpose, the hybrid AC/DC house is also designed in such a way to be entirely grid-independent to provide power …

Microgrid Energy Storage Branch, Evan Luu, Jeffrey Shieh

Electrical Engineering

The microgrid is the future for the electrical utility system. Because of this, future power engineers need to be well-versed in this topic when they go into industry. Cal Poly has created a microgrid laboratory for this very purpose. However, it is missing its battery based energy storage branch. Due to safety concerns, a traditional chemical battery is not suitable for student use. In order to maintain Cal Poly’s learn-by-doing approach, an alternative solution must be implemented. A regenerative power supply meets the criteria for student use. It is capable of simulating the sinking and sourcing capabilities of a battery …

Load Slammer Design For Dc-Dc Converter Testing, Jonathan Hidalgo, Quinton Lacomb

Electrical Engineering

In this work, we dive into the detailed design of a test load or load slammer circuit for DC/DC converters to ensure their correct functioning. This is accomplished through quick variations in frequency, amplitude, and duty cycle of the current being drawn by the converter into the load. Computer simulations of the design were performed using LTSpice and the results show that the load current could be varied per design objectives. Hardware implementation of the design was also conducted and then tested. Results were then compared with the design requirements at lower currents to evaluate the validity of the design. …

Ac/Dc Led Light Bulb Adaptor With Internal Rechargeable Batteries, Esteban A. Rubio, Matthew R. Delaby

Electrical Engineering

To make a sustainable product and provide a temporary source of lights on during emergencies, this project aims to create a small unit that can be attached to a light bulb of any variety and connect it to a socket. Within the device is a rechargeable battery that, when the device is not connected to an 120V AC, 240V AC, or 48V DC power source, will power the light for a short period of time. The battery can be charged during the standard operation of the device and can be powered by the US and EU standard outlet voltages as …

Solar Pv Emulator, Tristan Studer, Cody Kremer

Electrical Engineering

The implementation of a solar PV emulator. Creating a controllable testing environment which sufficiently recreates realistic conditions a photovoltaic cell would experience in real world use. The project aims to accurately show the efficiency and reliability of a solar PV cell, opposed to an ideal model which creates unrealistic expectations. The PV emulator implements conditions such as: irradiance, soiling and temperate changes. It gives feedback on a displayed IV curve and/or PV curve so the user may graphically analyze the output their PV cell produces given various conditions. It allows the user selectable conditions the solar cell may experience this …

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 …

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. …

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 …

2021 Department Of Energy Collegiate Wind Competition Electrical System, Grayson Capers, Shane Alayvilla, Justin Rodrigues

Electrical Engineering

In this work, the implementation of the electrical system for Cal Poly’s 2021 Department of Energy Collegiate Wind Competition turbine is described. The mission of this project was to complete the turbine testing tasks to the best of the team’s ability. This system includes an off the shelf slotless permanent magnet synchronous generator and rectifier to produce a DC voltage. To maximize the power output at below-rated wind speeds, current sensors, voltage sensors, and a dynamic load with variable resistance were designed and tested. To curtail the power and rotor speed in high wind events, the turbine was equipped with …

Hybrid Ac/Dc House, Vinh Q. Tran, Casey Winans, Erin O'Rourke

Electrical Engineering

The Hybrid AC/DC house is a proof of concept implementing a DC bus in residential power systems. The implementation of the DC bus is motivated by efficiency through a direct path for DC sources and loads. The avoidance of DC-to-AC and AC-to-DC conversions used in typical residential systems especially those with DC sources such as solar panels could experience higher efficiencies through only DC-to-DC conversions between the sources and the loads.

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. …