Power and Energy Commons^™

Analysis Of An Improved Reliability Dual-Buck Structured Three-Level Flying Capacitor Inverter, Almachius Kahwa Dr.

Tanzania Journal of Engineering and Technology (TJET)

With the increased demand for high-reliability power converters in the electric drive-train and propulsion systems, the efforts to design and analyze converters with high fault tolerance have become apparent. Among the emerging trends to improve the reliability of power converters is the incorporation of dual-buck (DB) structures in traditional converter topologies. Thus, this paper studies a single-phase dual-buck structured three-level flying capacitor (FC) inverter. The dual-buck flying capacitor (DBFC) inverter was constructed in such a way as to suppress the shoot-through problems that may occur because of the switching mismatch and gate driver delay, as exhibited in the traditional FC …

Calibration Of Measurement Tools In The Experimental Test Rig For Hydropower Performance Evaluation, Ombeni J. Mdee

Tanzania Journal of Engineering and Technology (TJET)

The demonstration of a typical hydropower plant requires the development of a test rig with the installation of tools to measure the performance parameters. The measurement tools require a calibration process to improve the quality of recorded data. This study involved the calibration of traditional and automated measurement tools connected to the hydropower test rig through an Arduino microprocessor. The automated measurement tools included a pressure transducer, flow meter, digital tachometer, and torque transducer, while traditional measurement tools, including a pressure gauge, concrete water tank, contact tachometer, and force lever arm balance, were connected in the same test rig during …

Review On Gas-To-Liquids Conversion Technology: Lessons From Case Studies And Potential Strategies For Implementation In Tanzania, Joseph H. Kihedu

Tanzania Journal of Engineering and Technology (TJET)

This review paper explores the transformative potential of Gas-to- Liquids (GTL) technology for harnessing Tanzania's vast natural gas resources. With significant discoveries of natural gas reserves totalling up to 57 Tcf in fields such as Songosongo, Mnazi Bay, Block 1, 2, 3 and 4. Tanzania is positioned to leverage GTL technology to convert these resources into high-value liquid fuels like gasoline, diesel and naphtha. Review of GTL process, its products and applications has been done. By analysing successful GTL projects globally and drawing lessons applicable to Tanzania, this paper provides strategic recommendations for policymakers and stakeholders to foster GTL development. …

A Review Of Lithium-Ion Battery Capacity Fade Deceleration At Power Fluctuations In Renewable Energy Systems, Isaac Gwayi

Tanzania Journal of Engineering and Technology (TJET)

Application of lithium-ion (Li-ion) batteries to store energy in renewable energy systems (RESs) is increasing due to their promising properties. Therefore, it is crucial to understand aging behaviours of Li-ion battery during RES life time as this directly affects cost of energy. Li-ion battery aging can be categorised into calendar aging and cycle aging. Calendar aging depends mainly on temperature and state of charge (SoC). In addition to temperature and SoC, cycle aging depends also on charge and discharge current rates and cut-off voltages. Higher current rates lead to faster Li-ion battery aging. It is necessary to identify appropriate battery …

Assessment Of Maintenance Performance Level Of Selected Hydropower Plants In Tanzania, Mahamudu H. Mtebwa

Tanzania Journal of Engineering and Technology (TJET)

Despite significant progress in increasing electricity access to over 78%, electricity reliability in Tanzania remains a concern, with frequent power outages reported. Maintenance issues in hydropower plants have been identified as a critical factor contributing to this problem. However, the specific maintenance performance levels have not been fully assessed. This study conducts a comprehensive evaluation of the maintenance performance of four key hydropower plants: Kidatu (204 MW), Kihansi (180 MW), Mtera (80 MW), and New Pangani Falls (68 MW). Data collected from staff surveys and maintenance records between 2018 and 2022 were used in the study. Although staff demonstrated a …

Potential Use Of Pump As Turbine Coupled To Self-Excited Induction Generator For Micro-Hydro Cooking And Cooling Applications, Emanuel J. Nyirenda

Tanzania Journal of Engineering and Technology (TJET)

Clean cooking and efficient cooling in developing countries have recently become areas of great focus. Further, the environmental impact of flooding in high-capacity hydroelectric plants has become a major concern. As a result, there is growing emphasis on developing sustainable and decentralized energy solutions, focusing on the potential of micro-hydro systems, especially in rural and remote areas. Although there are several alternative energy generation methods, their application is not straightforward. One of the latest technologies under research is using pumps as turbines coupled to an induction generator. This paper explores through a rigorous experimental approach the possibility of using a …

Optimal Placement Of Distributed Generation Units In Power Distribution Networks Using Particle Swarm Optimization, Owdean M. Suwi

Tanzania Journal of Engineering and Technology (TJET)

Power losses and voltage drops in distribution networks are critical issues in power system operation, reducing efficiency, reliability, and overall quality of the power supply to customers. Additionally, the rising electricity demand, deregulation of energy markets, and congestion in transmission networks have further contributed to the declining performance of the grid. To address these challenges, integrating distributed generation units (DGUs) into electric distribution systems has gained significant attention. Furthermore, the integration of DGUs into conventional fossil fuel-based power plants is becoming necessary to reduce greenhouse gas emissions. However, proper placement and sizing of DGUs are crucial for achieving optimal benefits. …

Prospects Of Clean Cooking Energy In Africa - Transition Pathways And Implications, Joseph H. Kihedu Dr.

Tanzania Journal of Engineering and Technology (TJET)

Despite abundant renewable energy resources, African countries still suffer from energy poverty, particularly in cooking. Up to 2022, about 74% of the African population had no access to clean cooking energy. With focus to Sub-Saharan African population, 90% has no access to clean cooking energy which decrease by 7% when kerosene is included. Traditional cooking, which involves the use of charcoal and firewood, is associated with health problems, environmental degradation, socioeconomic issues, and gender inequality. Transitioning to clean cooking energy not only promises significant health benefits but also offers opportunities for sustainable economic development and environmental preservation. In this study, …

Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin

Journal of Electrochemistry

A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing. The necessity for its sophistication arises from the availability of multi-dimensional sensing signals. Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sensitivity and selectivity. This study aimed to elucidate the modification of an indium tin oxide (ITO) electrode with a viologen monolayer with an ordered orientation. Novel methods were developed to immobilize a viologen molecule bearing a carboxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide with N-hydroxy-succinimide (EDC/NHS). In the two methods …

Ambient Co2 Capture And Valorization Enabled By Tandem Electrolysis Using Solid-State Electrolyte Reactor, Yan-Bo Hua, Bao-Xin Ni, Kun Jiang

Journal of Electrochemistry

Electrocatalytic carbon dioxide reduction is a promising technology for addressing global energy and environmental crises. However, its practical application faces two critical challenges: the complex and energy-intensive process of separating mixed reduction products and the economic viability of the carbon sources (reactants) used. To tackle these challenges simultaneously, solid-state electrolyte (SSE) reactors are emerging as a promising solution. In this review, we focus on the feasibility of applying SSE for tandem electrochemical CO₂ capture and conversion. The configurations and fundamental principles of SSE reactors are first discussed, followed by an introduction to its applications in these two specific areas, …

Review Of Energy Storage Systems For Optimal Planning And Operation Of Microgrid Resources, Ibrahim M. Ibrahim Dr., Walid A. Omran Prof., Almoataz Y. Abdelaziz Prof.

Future Engineering Journal

Energy storage systems (ESSs) play a central role in microgrid (MG) research and are widely used in related studies. This is due to the many applications of ESSs that enhance the performance of MGs. These include power quality applications and energy management applications. This paper presents a literature review of various studies that address the use of ESSs in microgrid (MG) systems to perform functions aimed at enhancing overall performance. These studies are classified into two main categories: planning and operational planning, with the MG being either grid-connected or islanded in each case. Finally, the optimization techniques used to obtain …

Design And Development Of A Half-Bridge Llc Resonant Converter Laboratory Module, Alyssa Lam

Master's Theses

Resonant DC-DC converters have become a well-known solution in power supplies due to their ability to improve efficiency by utilizing soft-switching techniques. This further has caused a growing interest in industry to use these converters for high-switching-frequency, high-efficiency, and high-power applications such as EV charging stations, photovoltaic systems, battery chargers, etc. One particular resonant topology that has gained popularity in recent years is the LLC resonant converter. Due to the prevalent use of the LLC resonant converter, it is therefore crucial for students preparing for a career path in power electronics to become well-versed in the concept and implementation of …

Open Source Microgrid Integration, Zachary J. Kwast

Master's Theses

Microgrids are small-scale electrical systems that operate in tandem with a centralized grid to provide power to a smaller group of target devices. These microgrids are used for a wide range of different purposes, which invites the need for a generalized model that can be tweaked for a variety of uses. This document goes over the theory used to design an open source AC and DC microgrid meant for use by anyone. The microgrid is created using a Raspberry Pi that controls two different power converters so that a wide range of voltage and current characteristics can be achieved. These …

Expeditionary Ocean Power Generator, Ethan Gossard, Julian Steele, Alex Gray, Hunter Herring-Alderete

Electrical Engineering

Point Absorber Wave Energy Converters are currently being explored as a new form of energy harvesting. The Naval Facilities' Expeditionary Ocean Warfare Center (NAVFAC EXWC) has commissioned an interdisciplinary project for students at California Polytechnic State University, San Luis Obispo, to design a prototype Expeditionary Ocean Power Generator (ExOPG) for charging batteries in the ocean.

The Mechanical Engineering team is responsible for assembling the prototype chassis, which converts the vertical bobbing motion of a buoy into kinetic rotational energy that can be used to rotate a generator shaft. They are additionally tasked with isolating the electrical components from the harsh …

Piezoelectric Actuator Driver System, Daniel Hoefer

Electrical Engineering

This work presents the design, fabrication, and testing of a high-voltage piezoelectric actuator driver system purposed for integration into defense and aerospace precision motion control applications, particularly those in laser optics. The core challenge addressed was the mismatch between the standardized 28V DC power bus used in military systems and the significantly higher voltage requirements of piezoelectric actuators. Existing commercial drivers were evaluated and found unsuitable for field deployment due to inadequate ruggedness, excessive complexity, or power limitations. Consequently, a modular system architecture was designed featuring four independent driver channels, each using a high-voltage, high-current linear amplifier topology to scale …

Marine Energy Collegiate Competition - Polywave Energy, Beneda Loya, Isaiah Martinez, Emily Nicoletta, Michael Weber

Electrical Engineering

This document is the final Electrical Engineering senior project report for Cal Poly’s 2025 Marine Energy Collegiate Competition (MECC) team. The goal of this project is to build and test a wave-energy converter designed to address the need for sustainable power generation for remote coastal community microgrids. These existing systems often rely on costly, fossil-fuel generators, creating both logistical and environmental challenges. Our device aims to provide a renewable, low-maintenance solution that can operate reliably in offshore environments and serve commercial or research applications. The goal of the electrical engineering team was to develop a system that can convert rotational …

Advanced Light Dimming Power Converter, Jaden Nguyen, Edwin Lin, Alan Thai

Electrical Engineering

This senior project discusses and follows the development of the Advanced Light Dimming Power Converter meant to modernize the power electronics curriculum and improve student safety for a lab. The power converter attempts to replace the original experiment which includes a traditional TRIAC-based dimmer and focuses on demonstrating phase angle control for incandescent light bulbs. However, several drawbacks including high-voltage exposure and outdated technology warranted a revamp. The redesigned module includes a dual-experiment setup with an updated TRIAC-based dimmer circuit and a new AC-DC LED driver circuit with constant current control and PWM dimming capability. Both systems have been fabricated …

Design, Analysis, And Implementation Of An Improved Zero Voltage Switching Hybrid Voltage Divider, Luke V. Cerda

Master's Theses

This thesis entails the study, design, and construction of a novel DC-DC converter topology, the Zero Voltage Switching Hybrid Voltage Divider (ZVS-HVD), with improved modularization, optimization, and compactness. The ZVS-HVD facilitates higher load currents and accomplishes DC-DC voltage division through switching inductors and capacitors. Low switching loss is achieved through zero voltage switching (ZVS) and the use of GANFET switches. An analysis of duty cycle and high-frequency operation is conducted, enabling 1 MHz switching and improvements in output voltage ripple, voltage drooping, board size, and efficiency at higher load currents. Two versions of ZVS-HVD prototypes were constructed with on-board signal …

Hydropower Collegiate Competition, Aiden D. Foster, Devon Bountry, Joanna Vo, Timothy Rinker, Amanda Rodriguez, Minh Nguyen, Eli Haushalter, Sophie Watkinson, Maiya Holton, Breanne Evans

Mechanical Engineering

The Cal Poly SLO HCC team presents a feasibility study and engineering design review package for retrofitting the non-powered Ritschard Dam in Colorado into a hydroelectric facility as part of the 2025 Hydropower Collegiate Competition. Through a rigorous and multi-staged assessment of plausible dam sites in the western US, the team has chosen the Ritschard Dam in Colorado to implement an electromechanical component designed to accommodate a large range of flowrates stemming from a large variance in upper reservoir capacity due to geographical and climate effects. The team evaluated non-powered dams based on technical feasibility, electric grid proximity, power generation …

Improvements To Cal Poly's Hybrid Ac/Dc House, Brandon Ng, Andrew Nguyen, Logan Tom

Electrical Engineering

This senior project details the improvements made to Cal Poly’s Hybrid AC/DC House project. The previous state of the house experienced issues with proper reading of the current power being drawn from the connected AC sources, as well as with the system’s multiple-input single-output converter, where thermal overheating of specific FETs prevented the system from reaching its maximum output power. The updates made to the AC/DC house include improved code to prevent faulty readings and display failure and a cleaned-up power monitoring board that removes noisy signals and allows for the correct power implementation to be displayed. In addition, the …

Compact Modular Photovoltaic System With Mppt Controller, Alain Ardash Kanadjian, Alex Aarnio, Christopher Arango

Electrical Engineering

Energy demands have been on the rise, as environmentally harmful power generation systems stay popular due to lower costs and compact designs compared to renewable energy infrastructure. We challenge this problem with a modular photovoltaic microgrid system for power generation in underutilized spaces. The Maximum Power Point Tracking (MPPT) charge controller employed is low-cost and power efficient. This controller monitors energy generation and usage in real time, with data logging through an online user-friendly interface. With support for a variety of solar panel and battery configurations, this scalable system helps provide a cost and space efficient solution to clean energy …

Development Of A Modular Dual-Phase And Single-Phase Buck Converter Laboratory Module, Maxwell John Kreizinger, Ethan David Robson

Electrical Engineering

This senior project entails the design, creation, and testing of a circuit board to exhibit the differences and advantages of the multiphase buck converter over the single-phase buck converter for use in a future power electronic laboratory experiment at Cal Poly State University. As energy demand requirements continually increase from more advanced and widespread use of technology, it is important to find a method of power delivery that maximizes efficiency while taking up as little area on a circuit board as possible. This is where the multiphase buck converter topology is desirable over the traditional single-phase buck converter topology. For …

Development Of A Versatile Switching Mode Inverter Laboratory Module, Zachariah Lee Mustar

Master's Theses

DC-AC converters, or inverters, are complex devices that play an essential role in photovoltaic, energy storage, and microgrid systems. Therefore, they constitute a class of power electronics that any power-focused electrical engineering student should be familiar with. This thesis presents the development and testing of a single device that power electronics students will use in a laboratory setting to experiment with each of the four different switching techniques employed in inverters: a simple square wave (SSWI), modified square wave (MSWI), bipolar PWM, and unipolar PWM. The module was built with a physically modifiable control stage and a power stage constituting …

Study On The Application Of Smart Electric Meters For Secondary Voltage Protection, Jayaditya Sisodia

Master's Theses

The purpose of our research is to utilize PG&E’s Smart Meters installed across California to protect the Secondary Voltage delivered to the meter. This means detecting electrical faults between the utility’s distribution transformer and the installed Smart Meter. Our goal is to propose and implement various solutions through additional devices and protocols to detect and prevent these faults, communicate them with the meter, and forward fault information to the utility. A device will be designed to be installed on the transformer, detect faults, shut off power transmission, and communicate to the meter via fiber optic cable. Research will then be …

Remote Monitoring And Control Of Protection Relays Via Programmable Logic Controller, Rio Mcgown-Kauffman

Master's Theses

The purpose of this study is to explore the ability of a programmable logic controller (PLC) to wirelessly monitor and control power protection relays. The technologies surrounding power protection and industrial automation are ever evolving and have developed significantly in recent history. Industrial power applications call for consistent condition monitoring and status updates for various high-importance components. The high-importance components have power protection schemes that are managed by digital relays to trip circuit breakers in fault or unsafe operating conditions. The smart relays have a wide range of capabilities, including communications. Cal Poly assembled a collection of relays from Schweitzer …

Modeling Battery Energy Storage Systems To Study The Effects Of Battery Chemistry And Operation On Power Quality, Lin E. Knudsen

Master's Theses

This thesis studies the impacts of battery chemistry (specifically lithium-iron phosphate, sodium-ion, and solid-state), AC voltage, battery size, charging mode, state of charge (SOC), active power draw, and power factor on the power quality of a Battery Energy Storage System (BESS). For harmonic evaluation, the metrics provided by the IEEE Standard 519 are used as a guideline to quantify voltage and current harmonics. A comprehensive MATLAB Simulink using Simscape Electrical is used to develop and simulate the models for the battery, DC-DC converter, AC-DC converter, and the grid. A total of 57 simulation cases varying the BESS factors are performed, …

Modeling And Efficiency Analysis Of Hybrid Ac/Dc And Conventional Ac House Electrical Systems For Net-Zero Energy Homes, Tyler Bury

Master's Theses

This thesis presents the design, simulation, and comparative efficiency analysis of hybrid AC/DC residential homes versus conventional AC homes for Net Zero Energy Homes (NZEH). Motivated by the increasing prevalence of DC-native technologies such as solar photovoltaics, battery storage, and DC-powered electronics, this work evaluates whether hybrid AC/DC distribution can offer measurable efficiency benefits over traditional systems. Twelve detailed house models were developed—six employing a hybrid AC/DC architecture and six based on conventional AC systems, each supplying a combination of AC and DC residential loads. Simulations were conducted using MATLAB/Simulink to model steady-state efficiency under various loading conditions. Grid configurations …

Price-Signal-Based Control Strategy For Heat Pump Water Heaters In Demand Response Applications, Othman A. Murad

Dissertations and Theses

This work presents a price-signal-based control strategy for residential Heat Pump Water Heaters (HPWHs) aimed at reducing electricity costs and shifting load away from high-price periods. By integrating the California Load Flexibility Research and Development Hub (CalFlexHub) prototype price signals, the Consumer Technology Association (CTA-2045-B) communication protocol, and the Object-oriented, Controllable, High-resolution Residential Energy (OCHRE) simulation framework, a rule-based controller was developed to align HPWH operation with dynamic electricity pricing while maintaining hot water availability.

The control strategy was evaluated through two case studies: one using a fixed water draw profile under varying levels of price signal foresight, and another …

Understanding The Morphology And Mass Transport Resistance Of Mesoporous Carbon-Supported Pemfc Based On Modeling Analysis, Hao Deng, Jia Liu, Zhong-Jun Hou

Journal of Electrochemistry

Mesoporous carbon supports mitigate Pt sulfonic poisoning through nanopore-confined Pt deposition, yet their morphological impacts on oxygen transport remain unclear. This study integrates carbon support morphology simulation with an enhanced agglomerate model to establish a mathematical framework elucidating pore evolution, Pt utilization, and oxygen transport in catalyst layers. Results demonstrate dominant local mass transport resistance governed by three factors: (1) active site density dictating oxygen flux; (2) ionomer film thickness defining shortest transport path; (3) ionomer-to-Pt surface area ratio modulating practical pathway length. At low ionomer-to-carbon (I/C) ratios, limited active sites elevate resistance (Factor 1 dominant). Higher I/C ratios improve …

Preparation And Modification Of Mxene Composites For Application In Electrochemical Energy Storage, Zhang-Hai You, Ding-Ze Lu, Kiran Kumar Kondamareddy, Wen-Ju Gu, Peng-Fei Cheng, Jing-Xuan Yang, Rui Zheng, Hong-Mei Wang

Journal of Electrochemistry

With the acceleration of advanced industrialization and urbanization, the environment is deteriorating rapidly, and non-renewable energy resources are depleted. The gradual advent of potential clean energy storage technologies is particularly urgent. Electrochemical energy storage technologies have been widely used in multiple fields, especially supercapacitors and rechargeable batteries, as vital elements of storing renewable energy. In recent years, two-dimensional material MXene has shown great potential in energy and multiple application fields thanks to its excellent electrical properties, large specific surface area, and tunability. Based on the layered materials of MXene, researchers have successfully achieved the dual functions of energy storage and …