This study presents a detailed investigation of the torque-speed characteristics of a WEG single-phase squirrel-cage induction motor (SPSCIM) of (1/2 hp), 110/220 V at 60 Hz. The primary objective was to derive the motor’s equivalent circuit and validate its performance curves through finite element analysis (FEA), simulation using MATLAB^®/Simulink^®, and experimental testing. Finite element simulations were conducted using the software FEMM (Finite Element Method Magnetics) to model the magnetic flux distribution within the motor’s stator and rotor. These simulations, based on the motor’s dimensions and nameplate data, provided essential insights into the electromagnetic behavior, including flux density and saturation effects, which are crucial for accurate torque-speed curve predictions. For experimental validation, tests were performed under open-circuit and locked-rotor conditions through a universal machine as a load emulator. The torque-speed characteristics were determined using the Suhr method and the classical approach, with the resulting curves compared to experimental measurements. Voltage and current were measured using AC PZEM-004T and DC PZEM-017 meters, while rotor speed was monitored with a Hall effect sensor (A3144). The results revealed strong agreement between the FEM simulations, Surh method, and experimental data, demonstrating the reliability and accuracy of the combined simulation and analytical methods for modeling the motor’s performance. The estimations using classical and Suhr methods, Simulink simulations, and FEMM yielded low error percentages, mostly below 2%. However, in the FEMM simulation, rotor resistance showed a higher error of around 20% due to unavailable data on the exact number of windings turns, a modifiable parameter that can be corrected through further adjustments in the simulation. The torque-speed curves obtained at different voltage levels showed an excellent correlation, confirming the effectiveness of the proposed approach in characterizing the motor’s operational behavior.

This study addresses the critical need for efficient laboratory methods to test battery performance, identified through a bibliometric analysis of research trends in battery technologies, integration challenges, lifespan, and recovery. A key focus is the detailed evaluation of lead-acid batteries and battery emulators in electronic applications. The study highlights the significance of lead-acid battery discharge emulators as cost-effective and safe alternatives to actual batteries in laboratory testing, enabling controlled testing conditions. The system behavior was validated by employing a resistive load module and making comparisons with manufacturer data. Using this system and a resistive load module, its behavior was verified by comparing it with the data provided by the manufacturer. The next phase of this work involved selecting components to emulate the battery's behavior using a switched-mode power supply controlled by a current source and a mathematical model chosen from the Matlab-Simulink tool through a Hardware-in-the-loop (HIL) system that interprets the battery's state of charge (SoC) to match the pre-configured model response to the lead-acid battery manufacturer's data. The emulator circuit was thoroughly evaluated against the model's expected responses to various charge levels, culminating in the implementation of an integrated prototype that simulates the discharge of lead-acid batteries in low-power applications and introduces a user-friendly interface, facilitating its application in general engineering studies. The work offers a valuable tool for battery research and development, promoting advancements in the study of lead-acid battery discharge in low-power applications.

This article presents a comprehensive analysis of the impact of the 'Parque Solar Salinas' photovoltaic (PV) plant on the medium voltage grid of Emelnorte S.A., a power distribution company located in the northern region of Ecuador. The main objective was to evaluate the power quality delivered by the plant, in compliance with the standards set by the Electricity Regulation and Control Agency of Ecuador (ARCONEL). The study was based on a detailed review of electrical generation, specifically focusing on solar PV energy. The components and topologies of PV plants, such as inverters, solar panels, and transformers, were described in depth. Additionally, the National Electrical Code regulations related to power quality were analyzed. The technical details of the plant is described, and the steps to determine the power quality are presented in the grid. Data were extracted from the plant, including variables such as active power, reactive power, voltage, and current. Short-term (Pst) and long-term (Plt) flicker were also analyzed and interpreted about solar radiation. The results obtained in this study were presented in a technical procedure manual that allowed for the evaluation of power quality for a photovoltaic plant when connected to a medium voltage grid.

This study investigates the performance of a 1.5 kW, 20,000 r/min universal motor under AC and DC supply by combining experimental characterization, MATLAB/Simulink modeling, and two-dimensional magnetostatic analysis using Finite Element Method Magnetics (FEMM). A motor–generator test bench was used to record electrical variables and shaft speed at different load levels, from which electromagnetic torque was estimated. Simulink represented the average electromechanical response through a lumped-parameter model, whereas FEMM was used to examine flux distribution, magnetic saturation, and rotor-position dependence. The experiments and Simulink model consistently showed decreasing speed and increasing torque as load increased, whereas FEMM clarified the associated magnetic saturation and rotor-position dependence. Simulink reproduced the general operating trends but exhibited quantitative deviations associated with its linear magnetic representation. FEMM indicated the onset of saturation between 2 and 3 A and showed that the calculated torque depended strongly on angular position. The coordinated comparison clarifies the complementary scope of experimental, system-level, and field-based analyses while identifying the limitations imposed by indirect torque estimation and magnetostatic modeling.

Low-frequency acoustic fields—common in ventilation ducts, building façades, and industrial infrastructure—remain an underutilized source for ambient energy harvesting, particularly in humid environments where conventional contact-based or mechanically resonant harvesters may degrade over time. This study introduces a theoretical framework for converting acoustic pressure oscillations into electrical power through acoustic–electrokinetic coupling and proposes the Acoustic Baroionic Harvester (ABH) as a solid-state concept combining a Helmholtz resonator with a charged nanoporous membrane. The model is derived from coupled electrokinetic and fluid-mechanical governing relations, leading to closed-form expressions for the open-circuit voltage, internal electrokinetic resistance, and maximum deliverable power as functions of membrane surface charge, electrolyte properties, pore geometry, and resonance-induced pressure amplification. Numerical simulations are performed to validate the analytical scaling laws and to determine operating regimes that maximize power transfer to an external load. Under representative low-frequency acoustic excitation, the ABH predicts open-circuit voltages on the order of tens of millivolts and maximum power densities in the sub-microwatt-per-square-centimeter range. A compact CAD conceptual design tuned to approximately 120 Hz with a moderate resonance quality factor supports the feasibility of practical integration. The proposed approach enables micro-power generation from persistent low-frequency acoustic sources and provides a physically grounded pathway for self-powered sensing applications in built and industrial environments.