Engineering Commons^™

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 …

Virtual Prototyping Of Pebb Based Power Electronics System For Ground Vehicles, Yi Li

All Theses

Power electronics are heavily involved in power and energy systems in plenty of applications nowadays. The increase of demand brings more challenges into simulations for development. Considering the complexity of the systems and high frequency operational conditions, this paper presents comprehensive research on modeling, simulating, and validation on ground vehicle propulsion system applications.

To reduce the computational burden, the Power Electronics Building Blocks concept is utilized to simplify the structure of modeling under different conversion scenarios in ground vehicle systems. In addition, the Average and Switching versions models are included. To speedup the simulation, the engagement of advanced computing technique …

Assessing Hardware Security Threats Posed By Hardware Trojans In Power Electronics, Quinn Kinzie

All Theses

This study investigates the threat of hardware Trojans (HTs) in power electronics applications, a rising concern due to the growing demand for cost-effective embedded solutions in power systems. With the supply chain for electronic hardware devices expanding globally, particularly to low-cost foundries in foreign locations, there is an increasing risk of HT attacks. While there has been extensive research on HTs in computer applications, little consideration has been given to their threat in power electronics. This study demonstrates the effectiveness of a power electronics HT by implementing a novel HT design into a gate drive circuit. Additionally, the research proposes …

Implementation Of Sic Power Electronics For Green Energy Based Electrification Of Transportation, Naireeta Deb

All Dissertations

Increase in greenhouse gas emission poses a threat to the quality of air thus threatening the future of living beings on earth. A large part of the emission is produced by transport vehicles. Electric vehicles (EVs) are a great solution to this threat. They will completely replace the high usage of hydrocarbons in the transport sector. Energy efficiency and reduced local pollution can also be expected with full implementation of electrification of transportation. However, the current grid is not prepared to take the power load of EV charging if it were to happen readily. Moreover, critics are doubtful about the …

Closed Form Implicitly Integrated Models For Computationally Efficient Simulation Of Power Electronics, Andrew Wunderlich

Theses and Dissertations

This work describes novel closed-form, implicitly integrated (CF-implicit) models of switched-mode power converters which feature implicit integration but require no iterative numerical solving algorithm for evaluation because they are explicitly solved prior to model execution. The derived models capture the large-signal dynamic behavior of the power converters, so their use and accuracy are not limited to any one set of operating conditions. These models can be implemented in any computational environment, including directly on an existing embedded controller as a digital twin. Since no iterative solver is required, the models are highly computationally efficient and have a very predictable worst-case …

Applications Of Laser Liftoff Technique For Wide Bandgap Power And Flexible Electronics, Md Didarul Alam

Theses and Dissertations

Wide bandgap (WBG) AlGaN/GaN and ultrawide bandgap (UWBG) AlGaN/AlGaN III-nitride high electron mobility transistors (HEMTs) have come a long way since their initial demonstration and are desired for a multitude of applications in deep-scaled high-frequency, high-voltage, high-current, and high-temperature power electronics. Although AlGaN/GaN HEMTs have recently become state-of-the-art in consumer electronics chargers and amplifiers, the performance of the devices is limited by severe self-heating which significantly reduce their efficacy in demanding applications that require high-current density. One strategy to reduce this self-heating effect in GaN HEMTs is to use high thermal conductivity SiC or bulk AlN substrates. While this approach …

Modeling Supercritical Fluids And Fabricating Electret Films To Address Dielectric Challenges In High-Power-Density Systems, Farhina Haque

Theses and Dissertations

Wide bandgap (WBG) devices and power electronic converters (PEC) that enable the dynamic control of energy and high-power density designs inevitably contain defects including sharp edges, triple points, and cavities, which result in local electric field enhancements. The intensified local electric stresses cause either immediate dielectric breakdown or partial discharge (PD) that erodes electrical insulators and accelerates device aging. With the goal of addressing these dielectric challenges emerging in power-dense applications, this dissertation focuses on 1) modeling the dielectric characteristics of supercritical fluids (SCFs), which is a new dielectric medium with high dielectric strength and high cooling capability; and 2) …

Load Modeling And Evaluation Of Leds For Hardware Test Bed Application, Jillian M. Ruff

Masters Theses

The lighting industry was revolutionized with the emergence of LED lighting. Over the last 15 years, LED lighting device sales and utilization have grown immensely. The growth and popularity of LEDs is due to improved operation of the device when compared to previous lighting technologies. Efficient performance of the device is critical due to the growth of global energy consumption.

As nonrenewable generation fuel is finite, utilities have begun the transition to renewable energy generation. Generation and distribution systems become inherently complex to comprehend and maintain with incorporation of emerging supply and load technologies. With the unprecedented growth of LED …

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 …

Current-Source Dc-Dc Converter For Fiber-Optic Communication Systems, Jissell C. Jose

Master's Theses

In this thesis, a proof of concept for a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter steps down an input current of 0.9 A to 0.625 A, while maintaining an output voltage of 24 V and output power of 15 W. The complete steady-state analysis and design of the proposed converter in its single-stage form is also explained in detail. Performance evaluation of the proposed converter was carried out using LTspice. Results of the simulation demonstrate that the design was able to produce average output current of 0.639 A at …

Nonmetallic Jet Impingement Thermal Management For Power Electronics Via Additive Manufacturing, Reece Whitt

Graduate Theses and Dissertations

The increase in energy demanded by transportation and energy sectors has necessitated highly efficient thermal management for reliable power electronics operations. Conventional cooling techniques are limited by their inability to target switching location hot spot temperatures, leading to non-uniform thermal gradients. These devices, such as cold plates and heat sinks, also utilize heavy metallic structures that can accentuate electromagnetic interferences generated by high voltage switching processes. This work proposes a non-metallic jet impingement cooler for more customized thermal management, while simultaneously reducing the harmful effects of electromagnetic interferences. Additive manufacturing is utilized to enable jet impingement zones to target individual …

Mission Profile Effects On Automotive Drivetrain Electronics Reliability: Modeling And Mitigation, Bakhtiyar Mohammad Nafis

Graduate Theses and Dissertations

The reliability of electronic devices is dependent upon the conditions to which they are subject. Temperature variations coupled with differences in thermal expansion between bonded materials results in thermomechanical stresses to build up, which can instigate failure in the interconnects or other critical regions. With the move towards electrification in the automotive industry, there is the increasingly important consideration of powertrain electronics reliability, the pertinent conditions being governed by the drive cycle or mission profile of the vehicle. The mission profile determines the power dissipated by the electronic devices, which determines the peak and mean temperature, temperature swing and the …

Analysis And Design Of 3-Phase Unfolding Based Ac-Dc Battery Chargers, Rees R. Hatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents the analysis and design of high-efficiency battery chargers for heavy duty EV applications. The rise in popularity of the electric vehicles (EVs) due to their increased efficiency over conventional internal combustion engines, has driven the need for more battery charging infrastructure. Furthermore, heavy duty vehicles are also being converted to electric to fill needs such as public transportation via bus fleets as well as cargo delivery via semi-trucks. Such heavy duty vehicles require more energy than personal transportation vehicles and thus require larger battery packs. To charge heavy duty battery packs in the same amount of time …

Characterization Of Wide-Bandgap Sic Field Effect Transistors And Their Active Gate Driving Circuit In High Power Applications, Arijit Sengupta

Legacy Theses & Dissertations (2009 - 2024)

Silicon Carbide (SiC) devices are slowly becoming one of the most reliable choices for high power density, high switching frequency applications with higher efficiency than Gallium Nitride (GaN) and Silicon (Si) devices. For a wide range of applications, such as Electric Motor Drives, Switching Power Supplies, and Renewable Energy Circuits, SiC devices are being tested and are found to yield prominent results.In this research, the characterization of two similarly rated commercially available SiC devices - a trench Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) and a cascoded Junction Field Effect Transistor (JFET) are done. It is followed by a comparative analysis of both …

Modular Multilevel Converters With Module-Level Energy Storage For Medium Voltage Applications, Bora Novakovic

Theses and Dissertations

This dissertation is on Modular Multilevel Converter (MMC) converter design and analysis and its integration with energy storage at the low voltage module-level. The developed converter concept and topology can be used in various applications especially for the support of intermittent renewable energy resources. The general converter structure is analyzed and extended to include integrated energy storage suitable but not limited to medium voltage applications. The behavior of the idealized structure is analyzed to obtain equations that govern general converter behavior and identify possible control loops. Detail mathematical switching model is developed for the MMC converter with generalized module structure. …

An Accurate And Efficient Electro-Thermal Compact Model Of Sic Power Mosfet Including Third Quadrant Behavior, Arman Ur Rashid

Graduate Theses and Dissertations

Due to narrower bandgap and lower critical electric field, silicon (Si) power devices have reached their limit in terms of the maximum blocking voltage capability. Exploiting this limitation, wide bandgap devices, namely silicon carbide (SiC) and gallium nitride (GaN) devices, are increasingly encroaching on the lucrative power electronics market. Unlike GaN, SiC devices can exploit most of the established fabrication techniques of Si power devices. Having substrate of the same material, vertical device structures with higher breakdown capabilities are feasible in SiC, unlike their GaN counterpart. Also, the excellent thermal conductivity of SiC, compared to GaN and Si, let SiC …

A Communications Testbed For Testing Power Electronic Agent Systems, Benjamin R. Dean

Masters Theses

As power electronic system (PES) continue to incorporate complex intra-system communication, understanding and characterizing this communication has become a complex task. Knowing how a system’s communication will behave is vital to ensuring proper operation of these systems. This thesis proposes and outlines a communication testbed that streamlines the development and testing of the communications between the components of PES, and further presents the characterization of communication protocol utilized in these multi-agent PESs. These communication protocols include MQTT, Modbus, or User Datagram Protocol (UDP). Understanding the different behavior of these protocols presents is paramount for the design of PESs.

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 …

Design And Evaluation Of High Power, High Efficiency And High Power Density Motor Drives For More Electric Aircrafts, Zhao Yuan

Graduate Theses and Dissertations

More-electric aircraft (MEA) is an attractive concept as it can reduce carbon dioxide emission, relieve fossil-fuel consumption, improve the overall efficiency of aircraft, and reduce the operational costs. However, it poses substantial challenges in designing a high-performance motor drive system for such applications. In the report of Aircraft Technology Roadmap to 2050, the propulsion converter is required to be ultra-high efficiency, high power density, and high reliability. Though the wide band-gap devices, such as the Silicon-carbide based Metal Oxide Silicon Field Effect (SiC-MOSFET), shows better switching performance and improved high-temperature performance compared to the silicon counterparts, applying it to the …

Developing A Medium-Voltage Three-Phase Current Compensator Using Modular Switching Positions, Vinson Jones

Graduate Theses and Dissertations

The objective of this thesis is to present the context, application, theory, design, construction, and testing of a proposed solution to unbalanced current loading on three-phase four-wire systems. This solution, known as the Medium-Voltage Unbalanced Current Static Compensator or MV-UCSC, is designed to recirculate currents between the three phases of adistribution system. Through this redistribution of the currents negative- and zero-sequence current components are eliminated and a balanced load is seen upstream from the point of installation. The MV-UCSC as it operates in the distribution system is presented followed by its effect on traditional compensation equipment. The construction of the …

Methods For Dynamic Stabilization, Performance Improvement, And Load Power Sharing In Dc Power Distribution Systems, Hessamaldin Abdollahi

Theses and Dissertations

Modern DC power distribution systems (DC-PDS) offer high efficiency and flexibility which make them ideal for mission-critical applications such as on-board power systems of All-Electric ships, electric vehicles, More-Electric-Aircrafts, and DC Microgrids. Despite these attractive features, there are still challenges that need to be addressed. The two most important challenges are system stability and load power sharing. The stability and performance are of concern because DC-PDS are typically formed by the interconnection of several feedback-controlled power converters. The resulting interactions can lead to destabilizing dynamics. Likewise, in a DC-PDS there are several source converters that are operating in parallel to …

Conducted Emi Mitigation In Power Converters Using Active Emi Filters, Balaji Narayanasamy

Graduate Theses and Dissertations

Wide bandgap devices enable high power density power converters. Despite the advantages of increased switching frequency, the passive components are still a major bottleneck towards enabling high power density. Among the passive components in the converter, the passive EMI filters are unavoidable to ensure compliance with conducted EMI standards. Active EMI filters help reduce the volume of the passive components and have been around for three decades now. Firstly, this work presents a summary of all the different active EMI filters based on the type of noise-sensing, noise-processing, the type of active circuits used and the type of control methods. …

Miso Dc-Dc Farmbot, Quyen Thi Nguyen, Brian Armijo, Astha Adhikari

Electrical Engineering

Making use of renewable energy directly from the location of production requires converting source power into usable power. The specific scope of this project focuses on the DC to DC conversion within a user friendly universal farmbot system. Since renewable sources vary widely in voltage and current, a wide input-range DC to DC converter is desired. Physical isolation, long lifespan, and adverse weather requires safe and reliable final product specifications. The goal of a very wide customer base drives the need for a product that does not require tinkering to get working, but to be usable out of the box …

A Hardware-In-The-Loop Platform For Dc Protection, Mark Vygoder

Theses and Dissertations

With the proliferation of power electronics, dc-based power distribution systems can be realized; however, dc electrical protection remains a significant barrier to mass implementation dc power distribution. Controller Hardware-in-the-loop (CHiL) simulation enables moving up technology readiness levels (TRL) quickly. This work presents an end-to-end solution for dc protection CHiL for early design exploration and verification for dc protection, allowing for the rapid development of dc protection schemes for both Line-to-Line (LL) and Line-to-Ground (LG) faults. The approach combines using Latency Based Linear Multistep Compound (LB-LMC), a real-time simulation method for power electronic, and National Instruments (NI) FPGA hardware to enable …

Cascaded Linear Regulator With Negative Voltage Tracking Switching Regulator, Ernest Lei

Master's Theses

DC-DC converters can be separated into two main groups: switching converters and linear regulators. Linear regulators such as Low Dropout Regulators (LDOs) are straightforward to implement and have a very stable output with low voltage ripple. However, the efficiency of an LDO can fluctuate greatly, as the power dissipation is a function of the device’s input and output. On the other hand, a switching regulator uses a switch to regulate energy levels. These types of regulators are more versatile when a larger change of voltage is needed, as efficiency is relatively stable across larger steps of voltages. However, switching regulators …

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 …

Energy Management Of Dynamic Wireless Power Transfer Systems For Electric Vehicle Applications, Ahmed N. Azad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wireless power transfer is a method of transferring electric power from a transmitter to a receiver without requiring any physical connection between the two. Dynamic Wireless Power Transfer (DWPT) entails having the transmitters buried under the roadway and the receiver unit being installed on the Electric Vehicle (EV). In this method, EVs are charged while driving over the transmitters as they receive bursts of electric energy at the time of significant alignment between transmitters and receivers. Compared to the stationary charging method which involves parking the EV for long hours for a full charge, the dynamic charging method (i.e., DWPT) …

Very Low Power Cockcroft-Walton Voltage Multiplier For Rf Energy Harvesting Applications, Trace Langdon

Electrical Engineering Undergraduate Honors Theses

A device was required that could harvest the electromagnetic energy present in ambient radio frequency (RF) signals. A part of this device must convert the AC RF signal received by the antenna into a DC signal that can be used in an embedded application. Since the RF signal amplitude is small, it must first be amplified and rectified to become a usable signal. The Cockcroft-Walton voltage multiplier is a subsystem of the design which ideally converts a 100 mV AC signal coming from the antenna to a 350 mV DC signal. The output of the voltage multiplier is used to …

Gating Methods For High-Voltage Silicon Carbide Power Mosfets, Audrey Dearien

Graduate Theses and Dissertations

The objective of this thesis is to assess the challenges associated with driving Silicon Carbide (SiC) power devices, and to compare the potential gate drive methods for these devices which address those challenges. SiC power devices present many benefits that make them suitable for next generation automotive, power utility grid, and energy management applications. High efficiency, increased power density, and reliability at high-temperatures are some of the main benefits of SiC technology. However, the many challenges associated with these devices have prevented their adoption into industry applications. The argument is made in this thesis that the gate driver is a …

Flexible Custom Electric Skateboard, Caleb Adam Kelsay

Electrical Engineering

At Cal Poly traveling long distances only accessible by foot such as across campus or from the car park to class can be tiring and time-consuming. While not physically demanding, the trek consumes time in our tight college life schedule. To improve our time efficiency this project provides a relatively lightweight, powered solution to quickly and effectively travel long distances while maintaining full control and safety even on hills, a current limitation of traditional skateboards.

This electric skateboard includes the battery capacity to travel all around campus on a single charge with a compact and flexible skateboard design that provides …