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. …

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 …

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 …

Conducted And Radiated Emi Measurements Of Parallel Buck Converters Under Varying Spread Spectrum Parameters, Elena Postupalskaya, Nathan Wang

Electrical Engineering

The Conducted and Radiated EMI Measurements with Parallel Buck Converters Under Varying Spread Spectrum Parameters research senior project aims to explore the effects from Spread Spectrum Frequency Modulation (SSFM) on the input electromagnetic interference (EMI) or noise of a switching power supply, specifically with LM53601MAEVM hardware. The input EMI is important as the main input bus needs to be clean to provide a reliable source for other sensitive devices connected to it. SSFM can replace a conventional EMI filter and save weight, space, and cost. This project provides a basis in terms of the impacts of variable SSFM in simulation …

Multiple Input Single Output Converter With Uneven Load Sharing Control For Improved System Efficiency, Kristen Y. Chan

Master's Theses

This paper presents the development and study of multiple-input single-output converter (MISO) for the DC House project that utilizes a controller to maximize the overall converter’s efficiency. The premise of this thesis is to create uneven load current sharing between the converters at different loading conditions in order to maximize the efficiency of the overall MISO converter. The goal is to find a proper ratio of current from each converter to the total load current of the MISO system to achieve the greatest efficiency. The Arduino microcontroller is implemented to achieve this goal. The design and operation of the MISO …

Cascaded Linear Regulator With Positive Voltage Tracking Switching Regulator, Brandon K. Nghe

Master's Theses

This thesis presents the design, simulation, and hardware implementation of a proposed method for improving efficiency of voltage regulator. Typically, voltage regulator used for noise-sensitive and low-power applications involves the use of a linear regulator due to its high power-supply rejection ratio properties. However, the efficiency of a linear regulator depends heavily on the difference between its input voltage and output voltage. A larger voltage difference across the linear regulator results in higher losses. Therefore, reducing the voltage difference is the key in increasing regulator’s efficiency. In this thesis, a pre switching regulator stage with positive voltage tracking cascaded to …

Pv Mppt Water Pump Controller, Jacob R. Lamkin

Electrical Engineering

The intention of this project is to create a low cost way to extract the maximum useful power from a PV module to power a water pump. This approach will yield maximum financial and technical accessibility for end users. The project was successful in powering a water pump from a PV module as desired, and the microcontroller driven control circuitry was capable of finding and maintaining operation at the maximum power point of the PV module. Due to the low performance of the buck converter used in this project, this approach was not as efficient as desired and would require …

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 …

Dc-Dc Buck-Boost Converter For Energy Harvesting From Exercise Equipment, David T. Bolla

Electrical Engineering

This senior project helps harvest the excess energy that exercise equipment generates. Sustainable energy acts as the main target for this project, and it attempts this through reusing the energy created when exercising on elliptical machines. An elliptical machine outputs voltages between approximately 5V and 60V, and a micro-inverter requires an input voltage of about 36V. This DC-DC converter takes the variable output voltage of an elliptical machine and brings it to approximately 36V. Re-purposing the excess energy an elliptical user creates for the grid provides a sustainable alternative to dissipating the energy as heat. This project, along with other …

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 …

The Zephyr Charge: A Wind-Powered Usb Charger, James Dean Carson, John Pina Lopez Iii

Electrical Engineering

The Zephyr Charge project is to design and build a cell phone charger using a small wind turbine generator that can be useful to the fishermen community, namely fishermen of third world countries. The generator will output to USB for ease of charging capability. The size of the whole system should be light enough to move around, and the turbine itself will be mountable onto an edge of a wall. The goal of this project is to design and build a compact and easy to use cell phone charger, which is also efficient.

In order to be a practical product, …

Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton

Master's Theses

This thesis investigates a relatively new method for harvesting wind energy by using flexible piezoelectric polymers with additional sails to increase their ability to harvest wind energy. This paper also introduces a new topology deemed the “stacked buck” that allows for multiple inputs to a system with a single output. Derivations and analysis detail the workings of the “stacked buck” with a laboratory test to show a working model. This paper also reports another experiment done in a wind tunnel to analyze the capability of the piezoelectric polymers as sources to the “stacked buck” topology with measurements of the power …

Analysis And Design Of Continuous Input Current Multiphase Interleaved Buck Converter, Sean Michael Zich

Master's Theses

The power requirements for microprocessors have been increasing per Moore's Law. According to International Technology Roadmap (ITRS), Voltage Regulator Module (VRM) for microprocessors will be about 200 W at 1 V output in 2010. With the VRM’s topology of synchronous buck, serious technical challenges such as small duty cycle, high switching frequencies, and higher current demands, contribute to decreased power density and increased cost.

This thesis proposes a Continuous Input Current Multiphase Interleaved Buck topology to solve the technical challenges of powering future microprocessors. This new topology is aimed to improve past topologies by providing continuous input current and improved …