Electrical and Electronics Commons^™

Voltage-Related Power Quality Issues And Impacts On Distribution Networks With Sensitive Loads - A Review, Godwin Elinazi Mnkeni, Jackson Justo, Aviti Thadei Mushi, Bakari M. M. Mwinyiwiwa

Tanzania Journal of Engineering and Technology (TJET)

Voltage disturbances are the most important power quality (PQ) complications that customers and power utilities face in this smart era. The growing adoption of sophisticated electronic equipment and integration of renewable energy sources (RES) into power grids has increased the susceptibility of power distribution networks (PDNs) to voltage sags, swells, interruptions, flicker, and voltage imbalance. These disturbances, mainly caused by upstream faults, switching operations, and RES integration, compromise voltage PQ and system reliability. Consequently, they accelerate equipment degradation, increase electronic waste (e-waste), raise reactive power demand and maintenance costs, increase power losses, and impose substantial economic losses on customers and …

Analysis And Design Of Multi-Winding Current Ballasted Magnetics For Integrated Dc-Dc Conversion, Kishalay Datta

Dartmouth College Ph.D Dissertations

Power conversion circuits have become a bottleneck in terms of reducing the size and cost of modern electronic systems in a vast number of applications ranging from personal devices, to automotive systems, to data centers. This has motivated designs at higher frequencies where smaller passive components can be used. Unfortunately, magnetic components scale poorly to smaller dimensions. In addition, the AC resistance of magnetic components deteriorates due to current crowding effects at high frequencies. This has resulted in fully- integrated power converters with planar magnetic components having efficiencies lower than what may be theoretically achieved. In this work, we investigate …

Disturbance-Learning Inertia Estimation Using Artificial Neural Networks For Power System Stability, Sospeter Igaanja Gabriel, Francis Mwasilu, Peter Makolo Dr.

Tanzania Journal of Engineering and Technology (TJET)

ABSTRACT

Power systems are progressively shifting towards low inertia as a result of incorporating significant amounts of intermittent and converter-based renewable energy sources, such as wind and solar power, into the current power grid network. This integration poses considerable problems to inertia and frequency control within the network due to a reduction in the proportion of synchronous generators. Furthermore, rapid frequency deviations occur due to the disparity between supply and demand during contingencies, complicating the maintenance of frequency stability within the power system. The disturbance-learning inertia estimation method for power system stability is presented. The simulation analysis is performed using …

Fast Sparse Image Reconstruction Models In Through-The-Wall Radars: A Review, Aude Kileo, Hashimu U. Iddi, Abdi Abdalla

Tanzania Journal of Science

Through-the-Wall Radar Imaging (TWRI) is a modern technology that uses electromagnetic waves to detect objects behind walls, with key applications in surveillance, rescue operations, and reconnaissance. Achieving high resolution in both down-range and cross-range requires ultra-wideband signals and long apertures, resulting in large data volumes, increased acquisition time, and high memory demands. TWRI employs Compressive Sensing (CS) to reduce computational time, which has proved its significance in many recent TWRI applications. However, in CS, image reconstruction approaches shift the computational burden from the sensing stage to the recovery stage, which prolongs the reconstruction times, making it unsuitable in time-sensitive applications. …

Hybrid Transformer-Bilstm Model For Early Fault Detection And Multiclass Classification Of Wind Turbine Faults Using Scada Data, Hassan Y. Mkindu

Tanzania Journal of Engineering and Technology (TJET)

Early and accurate fault detection in wind turbines is essential for improving operational reliability, reducing maintenance costs, and minimizing unplanned downtime. This study proposes a Hybrid Transformer-BiLSTM deep learning model for early fault detection and multiclass fault classification using Supervisory Control and Data Acquisition (SCADA) data. The proposed architecture combines the Transformer's self-attention mechanism to capture global temporal dependencies with the Bidirectional Long Short-Term Memory (BiLSTM) network's ability to model sequential fault evolution, enabling effective learning of multivariate time-series data. The model was developed and evaluated using the recently introduced CARE SCADA dataset, classifying five operating states: No Fault, Transformer …

Design Of Permanent Magnet Synchronous Motor For Railways Traction Application, Anna S. Mwang'onda, Jackson J. Justo, Francis Mwasilu

Tanzania Journal of Engineering and Technology (TJET)

This paper presents the design of surface mounted permanent magnet synchronous motor (SMPMSM) intended for traction applications in standard gauge railway (SGR) for passengers. The proposed motor is rated 350 kW with a base speed of 3000 rpm. Moreover, speed control strategy with stability analysis is incorporated in the design to validate the performance of the SPMSM. The simulation results achieved a torque of approximately 1115 Nm at a terminal voltage of 800 V. The flux linkage of 150 mVs which ensures effective electromagnetic pertinence while maintaining safe magnetic loading because the flux density is less than 1.5 T. The …

Flexible Power Point Tracking For Active Frequency Regulation In Grid-Connected Photovoltaic Power Plants, Castor K. Haule, Sophia D. Kigodi, Emmanuel S. Matee, Francis Mwasilu

Tanzania Journal of Science

The increasing penetration of photovoltaic (PV) systems into modern power grids necessitates advanced control strategies capable of supporting grid stability. Traditional PV systems rely on Maximum Power Point Tracking (MPPT) to maximize energy extraction, limiting their ability to participate in grid-support functions such as frequency regulation or power curtailment. This paper presents a flexible power point tracking (FPPT) control strategy that enables PV systems to operate at arbitrary points along the power–voltage (P–V) curve. A multi-mode power management scheme is proposed, integrating conventional Perturb and Observe (P&O) MPPT with FPPT, allowing the system to switch dynamically between energy maximization and …

Design And Characterization Of A 3d-Printed Dual Stacked Patch Antenna With Tunable Coupling For Uav Applications, Isabelle Lynn Brigman

Masters Theses

Antennas are a critical component of unmanned aerial vehicle (UAV) communication systems where compact size, light weight, and reliable operation across multiple frequency bands are critical. While microstrip patch antennas are attractive for UAV applications due to their low profile, low cost, and ease of fabrication, they are often limited by narrow bandwidth and fixed-frequency operation. To address these limitations, this thesis investigates a mechanically and electrically reconfigurable dual-stacked patch antenna fabricated using additive manufacturing techniques.

The proposed antenna consists of a slotted driven patch operating near 2.5 GHz with a second resonant mode near 5 GHz. A parasitic patch …

Effect Of Anode Size On The Properties Of Constricted Hollow Anode Pulsed Plasma Source, Nirav Patel, Garret Seckinger

Discovery Day - Daytona Beach

With the advent of ion thrusters, burns requiring large velocity changes can be performed with a fraction of the propellant required by traditional chemical rocket engines. However, current ion thrusters produce thrust in the order of millinewtons and thus cannot be viable for launching vehicles or burns requiring velocity changes in a small amount of time. Furthermore, current ion thrusters experience grid and component erosion, where the two grids at the termination of the nozzle slowly erode due to particle impact, and the hot electrodes degrade due to high thermal load. This limits the life of ion engines, which require …

Enhancing A Mid-Wave Infrared Fourier Transform Hyperspectral Imager For Explosions, James T. Stofel, Kody A. Wilson, Martin Larivière-Bastien, Anthony L. Franz, Michael L. Dexter

Faculty Publications

Capturing reliable hyperspectral imager data at a meaningful frame rate for explosions and other fast-changing scenes is not possible in the mid-wave infrared region under traditional sensor operating configurations and processing techniques, which typically have frame rates on the order of 0.5–2.0 Hz. To combat these shortcomings, the scene acquisition parameters were tailored for explosions and a new method for processing optical signatures of fast transient scenes with Fourier-transform infrared hyperspectral imagers was developed. For this technique, the instrument was first configured to collect asymmetric interferograms while optimizing the number of measurement points on the short side of the interferogram. …

Optimization Of A Cryogenic Electrical Characterization System And Its Application To Thermal Admittance Spectroscopy, Angel Efren Garcia

Open Access Theses & Dissertations

Defect characterization in semiconductors relies on locating trap levels through the temperature dependence of carrier emission, which makes the accuracy of the device temperature a limiting factor in every extracted parameter. This work addresses the limitations in the cryogenic electrical characterization system at The University of Texas at El Paso, where Deep-Level Transient Spectroscopy (DLTS) had been established but produced activation energies that disagreed with literature values by as much as 0.33 eV. The discrepancy was traced not to the technique but to the transfer of heat to packaged devices in a probe station designed for on-die measurement. The cryogenic …

Electrical Characterization Of Wide-Bandgap Devices Via Laboratory Measurements, Tcad Simulation, And Analytical Modeling, Sebastian Alessandro Mimbela

Open Access Theses & Dissertations

Gallium nitride (GaN) devices are important for high-power, high-frequency, and harsh-environment applications because of their wide bandgap, high breakdown capability, and electrical performance. This thesis focuses on the electrical characterization of GaN-based devices using laboratory measurements, analytical modeling, and TCAD simulation. Current-voltage (I-V) and capacitance-voltage (C-V) measurements were performed on a GaN Schottky diode. The measured data were analyzed to extract key parameters such as ideality factor, Schottky barrier height, series resistance, donor concentration, built-in potential, depletion width, and maximum electric field. A TCAD process was also developed in Synopsys Sentaurus to recreate the main geometry, layer structure, contacts, and …

Development Of Dynamic Proof-Mass Configurations For Broadband Piezoelectric Energy Harvesting, Nico E. Galarza

Electrical and Computer Engineering ETDs

The purpose of this thesis is to investigate and develop dynamic proof-mass configurations for broadband piezoelectric energy harvesting. Conventional piezoelectric energy harvesters are typically limited by narrow operating bandwidths, restricting their performance under variable-frequency excitation. This research presents the design, fabrication, and experimental evaluation of multiple proof-mass concepts intended to increase the usable frequency range of cantilever-based piezoelectric energy harvesters. Several dynamic mass configurations were developed using additive manufacturing techniques and integrated with commercially available piezoelectric cantilevers. Experimental testing was conducted under controlled vibration conditions to characterize voltage response, resonant behavior, and bandwidth performance. The results demonstrate that dynamic proof-masses …

Development Of Proposed Airworthiness Certification Criteria For Interference-Tolerant Radio Altimeter Systems, Matheus B. Furstenberger

Student Works

Radio altimeters provide height-above-ground information to flight deck displays and multiple safety-critical aircraft systems, however legacy certification standards were not developed for high-power terrestrial wireless services operating in adjacent C-Band spectrum. This study addressed the absence of a consolidated airworthiness certification framework for interference-tolerant radio altimeter systems installed on Title 14 Code of Federal Regulations Part 25 transport category airplanes. An archival research synthesis was conducted using publicly available regulations, proposed and final rules, technical standard orders, advisory circulars, airworthiness directives, industry standards, spectrum-management documents, technical studies, and stakeholder comments. Qualitative content analysis and source triangulation were used to identify …

Application Of Palmprint Data For Prediction Of Diabetes, Ramasamy K Mr

Theses and Dissertations

Type 2 diabetes is one among the diabetes mellitus which has strong relation with lifestyle, genetics and metabolic dysfunction. The increasing global prevalence, rising healthcare costs, and high percentage of undiagnosed individuals leads to the need of noninvasive, cost-effective early detection methods. In conventional diagnostic methods, laboratory investigations and periodic clinical visits are needed, which may not be feasible for working and middle-aged populations. To overcome this, the research work proposes an automatic, non-invasive and early prediction of Type 2 diabetes using palmprint image analysis integrated with clinical data for identifying diabetic and non-diabetic individuals. The first proposed method aims …

Dc/Dc Converter For A Solar Module, Francine Therese A. Canal, Jesus Cruz, Juan Jose Gonzalez

Electrical Engineering

This project presents the design and implementation of a DC/DC power converter intended for photovoltaic (PV) modules with varying electrical output characteristics. Solar panels experience significant changes in output voltage and power due to variations in sunlight, temperature, and load conditions. To ensure reliable operation across a range of conditions, the proposed converter is capable of both step-up and step-down operation to accommodate solar modules with power ratings from 50 W to 450 W and open-circuit voltages between 10 V and 80 V. The system operates at load currents up to 10 A and provide a user-adjustable output voltage within …

Dc/Dc Converter For A Solar Module, Stella Uribe, Richie Zaragoza, Olivia Grace Tran, Phillip Tyler Rich

Electrical Engineering

This project focuses on the design and validation of a general-purpose DC/DC power converter intended for use with photovoltaic (PV) solar modules operating under variable environmental and loading conditions. Solar panels exhibit significant variation in output voltage, current, and available power due to changes in irradiance, temperature, and operating point, making direct connection to downstream loads impractical. The proposed system addresses this challenge by providing a single, user-adjustable regulated DC output capable of both stepping up and stepping down the solar module voltage. The converter is designed to interface with solar modules rated between 50 W and 400 W, with …

Stationary Bike Power/Efficiency Monitor, Paula J. Diaz, Pilar M. Cook, Danielle Rhind

Electrical Engineering

This project developed a real-time power and efficiency monitoring system for a SportsArt ECO-POWR stationary exercise bicycle. The goal was to measure rider mechanical power and electrical power delivered to the utility grid simultaneously, allowing the overall bike-to-grid efficiency to be calculated and displayed in real time. Rider power was measured using Garmin Rally ANT+ power pedals, while grid power was measured using a Yokogawa WT310E power analyzer. A Raspberry Pi 3 Model B+ synchronized both data sources, calculated efficiency, displayed live performance metrics through a graphical user interface, and logged measurement data to CSV files for later analysis. The …

Autonomous Terrain-Mapping Robot For Search And Rescue, Soumil Joshi, Seann Calub

Electrical Engineering

This report documents the design, modular testing, and challenges faced while developing an autonomous terrain-mapping robot intended to navigate to a destination waypoint and deliver a small payload for search-and-rescue applications. The system combines a LiDAR sensor, an IMU sensor, and a Raspberry Pi 3B as the onboard processor, and an ESP32 microcontroller interfacing with motor drivers over a four-wheel chassis. A companion mobile application was developed to enable remote control and monitoring of the robot over a WiFi hotspot connection. A lithium-ion battery pack supplies power to all onboard components, with power budgets verified against component datasheets. Testing progresses …

Understanding The Structural Drivers Of Useful Exergy Intensity, João Santos, Tiago Domingos, Tânia Sousa, Matthew Kuperus Heun, André Serrenho

University Faculty Publications and Creative Works

Energy-Economy Decomposition Analysis Across 112 Countries 1971-2020