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 …

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 …

Joint Channel And Phase Noise Estimation For Mmwave Ofdm Systems Using Adaptive Kalman Filtering, Kwame Salum Ibwe

Tanzania Journal of Science

This manuscript presents a joint channel and phase-noise estimation framework for millimeter-wave (mmWave) OFDM systems based on an adaptive extended Kalman filter (EKF). The proposed method formulates a unified state-space model that simultaneously tracks time-varying multipath channels and oscillator phase noise, a critical impairment in 5G NR frequency range 2 (FR2) and emerging 6G transceivers. An innovation-based covariance adaptation mechanism is introduced to enhance estimation accuracy while maintaining computational efficiency. Simulation results demonstrate that the proposed approach achieves up to a 5 dB SNR gain at a target BER of 10⁻³, maintains NMSE below 10⁻³ for linewidths up to 200 …

Hybrid Solar - Coal Thermal Energy System For Industrial Process Heat At Sayona Drinks Limited In Tanzania, Santos Kihwele, Elisha D. Bitesigirwe

Tanzania Journal of Engineering and Technology (TJET)

Over the past two decades, global efforts to mitigate pollution from conventional energy sources have intensified, with coal remaining a major contributor to carbon emissions. While fossil fuels cannot be eliminated from thermal generation in manufacturing industries, particularly in middle‑income countries such as Tanzania, they continue to dominate as the primary energy source. Industries including food and beverage, paper, textile, paints, chemicals, and pharmaceuticals require substantial thermal energy for heating and drying, and typically rely on coal and natural gas.This study introduces a unique application of a parabolic trough solar thermal system with integrated thermal energy storage, specifically tailored to …

Compact Low-Profile Dual-Band Microstrip-Fed Monopole Antenna For Wlan And Lte Applications, Hashimu U. Iddi

Tanzania Journal of Engineering and Technology (TJET)

The rapid advancement in wireless communication technologies has led to rising user demand for high-speed data transfer, seamless connectivity, and improved wireless communication efficiency. Therefore, it is inevitable to develop efficient and compact antennas which can support different frequency bands of various wireless system standards in mobile devices. A compact, low-profile microstrip-fed monopole antenna operating in dual bands, 2.45 GHz and 5.8 GHz, and suitable for WLAN and LTE applications is proposed in this study. The proposed antenna’s radiating element was carefully designed using slotting techniques and optimising the various parameters for achieving the required resonance frequency. The proposed compact, …

Optimal Design And Techno-Economic And Environmental Analysis Of A Hybrid Solar Pv-Battery-Generator System For Off-Grid Telecom Towers And Rural Households: Case Of Misughaa Village In Tanzania, Ibrahim Mwammenywa, Martha Mwaikenda

Tanzania Journal of Engineering and Technology (TJET)

Telecommunication services are pivotal for the socio-economic development of communities, regions, and countries. Extensive and reliable telecom infrastructure enables populations to leverage development opportunities and bridge the urban-rural divide. However, extending these services to rural areas often necessitates the deployment of telecommunication towers in locations lacking national grid access. Consequently, service providers typically rely on diesel generators (DG) for power, which introduces significant challenges. These challenges include a high operational expenditure (OPEX), rendering telecom services unaffordable for rural communities, and substantial environmental pollution from greenhouse gas (GHG) emissions. This study aims to present an optimal design, encompassing sizing and economic …

Voltage Profile Enhancement In Iliceto Shield Wire Scheme For Rural Electrification: Case Study Of Chalinze-Mbwewe Transmission Line In Tanzania, Ebeneza Chaula, Ibrahim Mwammenywa, Santos Kihwele

Tanzania Journal of Engineering and Technology (TJET)

Rural electrification faces challenges due to significant voltage drops over long transmission distances, affecting reliability and power quality. While the Iliceto Shield Wire Scheme (ISWS) offers a modern cost-effective solution, voltage stability remains a challenge. This study analyses voltage profile enhancement within ISWS, focusing on the Chalinze-Mbwewe section of the 132 kV transmission line, using LTSpice simulations. Due to LTSpice limitations, direct solar PV integration was mimicked by introducing a secondary voltage source at each load centre, producing 33 kV to match the original source voltage. This approach maintained improved voltage profile from Msoga Village to Mbwewe over 80.9 Kilometers. …

Load Flow And Fault Performance Evaluation Of Interconnected Minigrids In Uganda Using Digsilent Powerfactory, Prossy Mutesi, Santos Kihwele, Emmanuel Matee

Tanzania Journal of Engineering and Technology (TJET)

The increasing demand for decentralized, reliable electricity in rural Sub-Saharan Africa has catalyzed the deployment of minigrids as an intermediate electrification strategy. This study investigates two solar photovoltaic (PV) mini-grids: Kyamugarura and Kanyegaramire, located in western Uganda, approximately 3km apart. Each mini grid initially consisted of 13 kW installed photovoltaic (PV) capacity, supplying power to households and small businesses. Due to rising demand and regular evening blackouts, both mini-grids are being upgraded to 57 kWp each. The integration of these upgraded systems into the national utility grid is proposed and simulated to evaluate performance improvements under two medium-voltage interconnection options: …

Riki&Dolphin: Real Time Data Transmission From The Bottom Of A Cave To A Website, Luca Tringali, Giacomo Canciani Dr., Tecla Tripari, Alexander Debenjak, Caterina Bearzotti

International Journal of Speleology

Coming from over 10 years of experience in cave monitoring in northeast Italy, Gruppo Speleologico Talpe del Carso, has designed Riki and Dolphin: customizable, low cost, and easy to assemble tools for getting real time data transmission from the bottom of a cave, even underwater, to a webserver. Their use has been tested to monitor air temperature inside the Abisso Bonetti Cave (Classical Karst, Italy), proving for the first time that a cave in Gorizian Karst can systematically be colder than the outdoor temperature even in winter, recording an internal temperature even lower than 0°C. The Dolphin device can be …

The Pid-Based Three Quadcopter Uavs Formation Control Under External Disturbance, Vo Van An, Trinh Luong Mien

Makara Journal of Technology

This paper presents the design and evaluation of a formation control strategy for three quadcopter UAVs, based on a PID controller in a leader–follower structure, under the influence of external disturbances. Each UAV employs a six-degree of-freedom dynamic model and utilises a cascade PID control architecture, in which the inner control loop stabilises the attitude. In contrast, the outer control loop regulates position and maintains the formation. The PID parameters are tuned using the Ziegler–Nichols method to ensure simple implementation and low computational cost. The performance of the control system is evaluated through simulations in the MATLAB environment for two …

Condition Monitoring Of Induction Motor Using Motor Current Signature Analysis, Francis Ikechukwu Obianke, Joseph Okhaifoh, Benjamin Akinloye

Al-Bahir

Induction machines serve as the cornerstone and driving force of modern manufacturing and production systems. This research aims to monitor and analyse the operating performance of induction motors using motor current signature analysis (MCSA). MCSA is employed to process the current signal of a motor into a frequency spectrum, known as the current signature by applying the Fast Fourier Transform (FFT) algorithm. The underlying principle is that vibration generated in a motor is closely related to the changes of the magnetic field density, and the induced voltage varies with the stator current.

A simulation model replicating the behaviour of an …

Enhanced Cuckoo Search-Based Optimization For Single Distributed Generation Placement And Sizing In Radial Distribution Systems, Samson Oladayo Ayanlade, Abdulrasaq Jimoh, Richard Oladayo Olarewaju, Ignatius Kema Okakwu, Israel O. Adejumobi, Joseph B. Samson, Oluwadare A. Adebisi, Oluwadare O. Akinrogunde

Al-Bahir

This paper presents an Enhanced Cuckoo Search Algorithm (ECSA) to optimally place and size Distributed Generation (DG) in radial distribution systems to minimize real power loss within operating constraints. The proposed ECSA has exponentially decaying adaptive Lévy flights, constraint-aware solution repair with dynamic penalty coefficients, and diversity-directed stochastic replacement to enhance search robustness and convergence speed. It was tested with 30 independent runs on the IEEE 33-bus, IEEE 69-bus, and a practical Nigerian 32-bus distribution network. The simulations show that the ECSA lowers the active power loss of the IEEE 33-bus system from 201.58 kW to 102.75 kW (49.03%), and …

Voltage-Mode Driver With Sar-Based Termination Calibration, Moustafa M. Elsayed, Abeer T. Khalil, Sameh A. Ibrahim, Mohy Eldin A. Abo-Elsoud

Mansoura Engineering Journal

This paper introduces a DAC-based four-level pulse-amplitude modulation (PAM-4) driver capable of operating at data rates up to 80 Gb/s in 65-nm CMOS technology. A replica-based termination calibration loop is proposed to preserve driver linearity across process, voltage, and temperature (PVT) variations. The proposed driver achieves a relative level mismatch (RLM) of 99.3%. In addition, the transmitter demonstrates a vertical eye opening of 134.8 mV and a horizontal eye opening of 0.44 UI under worst-case conditions.

Reducing Range Anxiety Through Predictive Modeling Of Ev Battery Degradation, Caleb Thornsbury, Christian Castro, Bivin Sadler

SMU Data Science Review

Electric Vehicles (EV) range anxiety remains one of the top barriers for broader adoption. Range anxiety can be attributed to battery pack age and degradation over time. This paper plans to explore how to address this issue by creating a machine learning model that can predict degradation based on usage, temperature, battery chemistry, charging habits and exploring whether other factors tie into range degradation. This research will be using real world charging data along with lab tested chemistry data to build a model that can be chemistry specific for degradation. This paper will help perspective used-EV buyers learn about battery …

Research Of Logic Elements Based On Complementary Bipolar Transistors, Nodira Batirdjanovna Alimova, Nilufar Baxtiyorovna Gulyamova

Chemical Technology, Control and Management

Important parameters for any type of inverter – a NOT logic gate – are the power consumption during switching and the supply voltage. The proposed connection of complementary (two different types) bipolar transistors reduces the current consumption and supply voltage by simultaneously using the cutoff and saturation modes of the bipolar transistors. It has been theoretically and experimentally established that an inverter using complementary bipolar transistors operates at low supply voltages, approximately 0.7 V. Power consumption is virtually independent of the inverter's static state. A method for calculating the transfer characteristic of an inverter using complementary bipolar transistors is developed, …

The Main Errors Of The Ultrasonic Sensor In Measuring Water Flow In Open Channels, Anvar Urolovich Djalilov

Chemical Technology, Control and Management

This article analyzes the use of ultrasonic sensors in measuring water flow and the main errors that may occur in this process. In the conducted scientific research, a time-pulse ultrasonic sensor was tested. The absolute, relative and repeatability errors of the sensor during water flow measurement were studied. The absolute error represents the largest difference between the value recorded by the sensor and the real value, affecting the overall accuracy of the measurement system. This error can vary depending on environmental factors, the design and operating principles of the sensor. During the experiment, the performance of this sensor was …

Synthesis Of An Adaptive Synergistic Fuzzy Discrete Controller For Nonlinear Systems, Isamidin Xakimovich Sidikov, Gulruxsor Murot Qizi Nashvandova, Feruzakhon Botirxon Qizi Sodiqova

Chemical Technology, Control and Management

The paper considers the issues of synthesizing an adaptive fuzzy synergetic controller with discrete time for nonstationary nonlinear dynamic objects. The proposed approach is based on the integrated use of synergetic control principles and fuzzy logic methods, which ensure the formation of a control law for nonlinear dynamic objects that provides asymptotic stability of the control system. Such a hybrid combination makes it possible to guarantee the asymptotic stability of the closed-loop system and to shape the required dynamic behavior of the object over a wide range of operating modes. In addition, this approach provides the ability to adapt to …

Code-Net++: An Attention-Guided Deep Learning Framework With Grad-Cam-Based Explainability For Covid-19 Detection Using Chest X-Ray Images, Fareesa Amina, Dr Krishnanaik Vankdoth

Mansoura Engineering Journal

Chest radiograph imaging has emerged as a practical and scalable diagnostic modality for respiratory diseases, including COVID-19. However, accurate discrimination of COVID-19 manifestations from other pulmonary abnormalities remains challenging because of low contrast, imaging noise, and overlapping radiographic patterns. This work presents CODE-NET++, an enhanced attention-guided deep learning framework with Grad-CAM-based explainability for reliable COVID-19 detection using chest X-ray images. The proposed framework integrates adaptive trilateral filtering for image enhancement, Reverse Edge Attention Network (RE-Net) for lesion-aware segmentation, and an Enhanced LinkNet architecture with dilated convolutions for multiscale feature extraction and classification. Grad-CAM-based explainable artificial intelligence visualization is incorporated to …

Federated And Explainable Spiking Neural Networks For Fair And Privacy-Preserving Nail Disease Diagnostics, Ch Pavani Reddy, Krishnanaik Vankdoth

Mansoura Engineering Journal

Automated nail disease diagnostics provide a non-invasive pathway for identifying underlying systemic health conditions; however, conventional centralized deep learning approaches often raise concerns related to privacy, fairness, and interpretability. Although the original NeuroNail-SNN framework demonstrated an energy-efficient and edge-ready diagnostic solution, its broader clinical adoption remained limited by unresolved trust, transparency, and ethical considerations. In this study, we propose the Federated and Explainable NeuroNail-SNN, which extends the original spiking neural architecture by integrating federated learning (FL), explainable artificial intelligence (XAI), fairness evaluation, and uncertainty quantification within a unified framework. Federated learning enables decentralized model training across hospitals and mobile clinics …

Design, Optimization, And Techno-Economic Analysis Of A Standalone Pv-Wind-Battery Microgrid For A Remote Load In Kurdistan Region Of Iraq, Harwan Mohammed Taha, Laith Akram Mohammed

Mansoura Engineering Journal

Standalone microgrids play a crucial role in rural areas where grid electricity delivery is difficult and expensive. This research verifies the effectiveness of a standalone microgrid in a rugged area, Pers Mountain in Akre district, Duhok governorate, Iraqi Kurdistan. A first hybrid renewable energy system (HRES)-based standalone microgrid is presented to supply a remote load. Solar and wind energy are employed for their reliability, sustainability, and abundance, with battery storage ensuring continuous power when solar and wind are unavailable. Simulation results demonstrate reliable power supply during summer months (loss of power supply probability < 5%), with the system operating across three modes — PV-dominant daytime, combined wind-battery evening, and battery-discharge nighttime. The inverter achieved minimum total harmonic distortion of 1.53% for both current and voltage outputs, below the IEEE 519 limit. A full-year hourly particle swarm optimization (PSO) sizing analysis assessed annual reliability and each source's economic contribution: the original fixed sizing yields an annual loss of power supply probability (LPSP) of 26.80% (expected energy not served ~1,471 kWh/year), motivating a PSO-optimized PV-battery configuration achieving annual LPSP of 5% (~274 kWh/year unserved) at comparable cost. The site's wind resource is reasonable (13.8% capacity factor), but the fixed tower and controller cost outweighs its contribution at this small scale. The proposed HRES totals $11,960–$16,317 depending on configuration, approximately 28–38 times lower than grid extension ($455,600) to the site, while producing zero CO₂ emissions and avoiding approximately 4,189 kg/year versus an equivalent HOMER Pro-simulated diesel generator.

A Solar Pv System For Industrial Application- A Case Study Of A Cement Industry In Tanzania, Santos Kihwele

Tanzania Journal of Engineering and Technology (TJET)

This study presents an implementation of the largest behind-the-meter solar photovoltaic (PV) system for a cement industry in Tanzania. The project aims to supply energy for the industry’s own use, without any energy injection into the utility grid, for the purposes of cutting energy-related expenditure and reducing reliance on the utility grid. The project also aims to contribute to the efforts towards the application of renewable and alternative energy sources as a means to reducing carbon footprints, towards achieving the net-zero CO₂ emission goal. A comprehensive site assessment was conducted, analyzing factors such as location, land availability, climate data, …

Development Of An Iot-Based Energy Theft Detection System For A Single-Phase Smart Meter, Ojo Julius Oladele, Funso Kehinde Ariyo, Samson Oladayo Ayanlade, Ayooluwa Peter Adeagbo, Ismail Adeniyi Adeleke

Al-Bahir

Electricity theft causes annual global losses exceeding $96 billion, severely impacting distribution networks. This paper presents a novel IoT-based system integrating current differential sensing, physical tamper detection, and edge-cloud analytics to detect energy theft in single-phase smart meters. The design employs three ACS712 current sensors to monitor Kirchhoff-compliant current flow at the grid pole, meter input, and load output, coupled with a PIR sensor for cabinet intrusion. A SIM800L GSM module enables real-time theft alerts and remote disconnection, while closed-loop control autonomously restores power after tamper resolution — a feature absent in prior GSM-only systems. An Android application provides geotagged …

Analysing The Impact Of Bi-Directional Application Of Iliceto Shield Wire Scheme For Rural Electrification In Tanzania: A Chalinze-Hale Transmission Line Case Study, Santos Kihwele, Prisca Paul

Tanzania Journal of Engineering and Technology (TJET)

Clean energy accessibility including electricity remains a major challenge in Tanzanian villages despite the many efforts made by its government.  The primary obstacle is that these villages are located more than 100 kilometres away from high-voltage to medium-voltage (HV/MV) transformer stations. Therefore, electrifying these villages by conventional method is financially not feasible. One of the low-cost rural electrification techniques that can be used to solve the issue is the "Iliceto Shield Wire Scheme" (ISWS) technology, In Tanzania, the application of ISWS technology seems to be very promising.  However, the technology can be integrated with locally available renewable energy sources ( …

Experience With The Stem For Success Internship, Ujwal S. Thirunagari

STEM Month

In this article, I discuss my experience working with the STEM for Success team. I detail some of the challenges I faced in completing the CRT and LED sections, how I addressed these challenges, and the widely applicable skills that I learned.

Television Guidebook, Ujwal S. Thirunagari

STEM Month

In this television guidebook, we work to clearly explain television technology by including detailed illustrations and introducing fundamental concepts. This guidebook first explains the Cathode Ray Tube by laying out the basics of circuits, thermionic emission, the electron beam gun, and the deflection yoke. Then, the guidebook tackles the modernly adopted LED panel technology used in most phones and computers by explaining the fundamentals of light and liquid crystal. In future iterations of the guidebook, we hope to delve into more detail on color CRTs, thin film transistors, OLED panels, and Micro-LED technology.

A Light-Dependent Resistor Based Embedded Image Acquisition System For Use In Low-Resolution Application-Specific Data Processing, Connor Best

Journal of Undergraduate Research at Minnesota State University, Mankato

This paper proposes an efficient hardware-based approach to image acquisition & processing to replace complex camera systems in simple industrial & commercial applications.