The Eletrônica de Potência (Open Journal of Power Electronics), published by SOBRAEP, is a Gold Open Access journal with a single-blinded peer review process to publish original and unpublished articles. Since january of 2024, it has been published continuously. It aims to disseminate the latest technologies and theoretical research in the field of power electronics and inspire interdisciplinary research across academia and industry. Thus, our mission is to serve as a leading platform for the dissemination of research and innovations in the field of power electronics. The following list of topics is not intended to be exhaustive, but rather to indicate topics that fall within the journal purview: 1. Power converter topologies and design 2. Electrical machines, motor drives and motion control 3. Modeling, simulation and control in power electronics 4. Power quality, harmonics and reactive power compensation 5. Electromagnetic compatibility (EMC) and electromagnetic interference (EMI) 6. Power electronics in renewable energy systems 7. Power electronics in smart grid and utility applications 8. Power semiconductor devices, packaging and magnetic materials 9. Power electronics in lighting applications 10. Automotive, aerospace and transportation applications of power electronics 11. Industrial, commercial and residential applications of power electronics 12. Education and special topics Audience Researchers in academia and industry, electrical and electronic engineers Release of the Open Journal of Power Electronics In 1996, the SOBRAEP Deliberative Council proposed the release of an Open Journal, focused on Power Electronics and Electrical Drives, the Open Journal of Power Electronics. The first issue of the Open Journal of Power Electronics was released in June 1996 (vol. 1, n. 1), with the main objective of disseminating the national research in the field of Power Electronics, not only in the academic circles, but also in the productive/industrial environment. Major transformations were accomplished from 2003, both in terms of formatting and, mainly, implementing a fully electronic system to submit and analyze papers for the Open Journal of Power Electronics, called the iSOBRAEP system. The goal of increasing the visibility of the Open Journal of Power Electronics has become feasible with the development of the iSOBRAEP system, and with the transformation of the publication mainly to the electronic form, Open Access, distributed over the Internet, it was intended to increase the visibility of the Open Journal of Power Electronics, increasing its impact factor in bibliographical references. In 2018, several improvements were made aiming for indexation in the Scopus Database. The submission system was moved to the well-known ScholarOne Manuscripts, and a new website was built, including the Journal database. Another improvement was the DOI (Digital Object Identifier) attribution to all published papers by the Open Journal of Power Electronics since its first edition in 1996. Since December 2023, Eletrônica de Potência uses the CC BY 4.0, and since january of 2024, the frequency of publication was changed and it is published continuously. Besides, our editorial policy follows the research communication in the Open Science modus operandi
Small Signal Analysis of Rotating Reference Frame Based Synchronization Control for Microgrid to Grid Changeover
Reliable synchronization is essential for ensuring stability during the transition of microgrids between islanded and grid-connected operation, particularly in converter-dominated lowinertia systems. This paper outlines a small signal analysis for the novel synchronization control of an islanded microgrid comprising two or more parallel-connected voltage source converters. It focuses on the development of simple and effective microgrid synchronization strategies with a minimum Rate of Change of Frequency (ROCOF), enabling the integration of Distributed Energy Resources (DER) into growing low-inertia power systems. The proposed method is based on a rotating reference frame-based algorithm with two Proportional-Integrator (PI) controllers at the secondary control level, minimizing the computational complexity by reducing the number of control loops compared with conventional approaches. A small-signal model has been developed and validated using eigenvalue analysis to ensure stability during the mode transitions. The developed controls were validated on a test setup comprising of a 25 kW Grid-Forming Converter (GFC) and a 25 kW Grid-Following Converter (GFL).
Copyright (c) 2026 Deepak Gehlot , Shoubhik Mukherjee, A.S. Krishna Priya, Mukesh Kumar Pathak https://creativecommons.org/licenses/by/4.0
Modeling and Control of a Full-Bridge DC-DC Converter for Arc Welding Applications
This study presents the modeling and control of a full-bridge DC-DC converter applied to Gas Metal Arc Welding (GMAW) in short-circuit transfer mode. GMAW is widely used in industrial manufacturing due to its versatility. However, achieving stable operation in short-circuit transfer requires precise regulation of the welding current and arc voltage. To address this challenge, a simplified yet representative model of the converter and load dynamics is developed. Based on this model, a dual-loop digital control strategy is implemented to ensure fast transient response, reference tracking, and improved stability of the welding process. The effectiveness of the proposed approach is experimentally validated on an industrial-grade prototype, demonstrating agreement between theoretical predictions and measured waveforms.
Copyright (c) 2026 Christian G. Barbosa, Vitor de S. Guedes, Rafael C. Beltrame, Lucas V. Bellinas, Fábio E. Bisogno, Ezequiel A. Mallmann, Luciano A. Fricke https://creativecommons.org/licenses/by/4.0
Analysis and Design of a Half-Bridge Converter with Current Doubler for Auxiliary Power Modules in Electric Vehicles
Electric vehicles (EVs) demand highly efficient power management systems to enhance reliability and extend operational autonomy. Unlike traditional internal combustion engine (ICE) vehicles, which use alternators to supply low-voltage systems, EVs rely on DC-DC converters, commonly referred to as Auxiliary Power Modules (APMs). This paper presents the analysis, design, and experimental validation of a half-bridge converter with a current-doubler (HB-CD) topology tailored for APM applications. A generalized structure is proposed to support the parallel operation of multiple modules, aiming to mitigate current stress and reduce output ripple. A 3~kW laboratory prototype was implemented using two 1.5 kW modules operating in parallel, enabling interleaved operation and effective current sharing. Experimental results demonstrate the converter’s ability to maintain high efficiency, reaching up to 94.6 % under nominal conditions and 95.9 % under minimum input voltage operation, confirming the feasibility of the proposed topology for high-current automotive applications.
Copyright (c) 2026 Pedro H. B Löbler, Wellington G. R. Volz, Ademir Toebe, Cassiano Rech, Luciano Schuch https://creativecommons.org/licenses/by/4.0
Demand Response Program applied for Electric Vehicle Charging in Distribution Networks
The growing penetration of Electric Vehicles (EVs) poses new challenges to distribution system operation, particularly regarding peak demand and asset overloading. This paper proposes an optimization model for EV charging profiles based on time-varying and location-sensitive signals derived from the electrical impedance matrix of the distribution network. Building on a previously published tariff-sensitivity framework, this study develops an EV charging optimization model that uses nodal and hourly signals to reflect the marginal impact of current injections on line congestion. The optimization minimizes the total EV charging cost while mitigating adverse grid impacts. Simulation results using the IEEE 123-bus system demonstrate reductions in losses and line loading, as well as cost savings for EV owners. By combining the proposed approach with the existing tariff-sensitivity framework, Distribution System Operators (DSOs) can better align incentives for EV owners, without compromising their charging profiles, and mitigate network issues, thereby supporting the scalable integration of EVs.
Copyright (c) 2026 Delberis A. Lima, Leandra S. Almeida, Rafael S. D. Teixeira https://creativecommons.org/licenses/by/4.0
Bayesian Optimization-Based Tuning of the Proportional-Integral Controller for Grid-Connected Three-Level NPC Converter
Power converters provide energy interface in various applications; in photovoltaics, they interconnect solar panels to the grid, with two‑level inverters being the most common across virtually all power ranges, followed by three‑level neutral point clamped (3LNPC) converters. The proportional-integral (PI) controller is the most commonly employed controller for these converters. This paper proposes the use of Bayesian Optimization (BO) to tune the PI controller for a 3LNPC converter connected to the grid. The optimization algorithm was used to determine the controller’s tuning gains through computational simulation. Subsequently, the PI controller tuned using BO was implemented on an experimental test bench to validate the concept. The performance of the controller tuned with the proposed method was compared to PI controllers adjusted using classical methods widely found in the literature. The test results demonstrated that Bayesian Optimization is straightforward to implement and, when compared to the Genetic Algorithm (GA), it exhibited a more effective and targeted exploration of the search space. This led to superior PI controller tuning, with improved dynamic response and reduced total harmonic distortion relative to the benchmark methods.
Copyright (c) 2026 Vitor S. Jorge, Angelo S. Lunardi, Luan A. Sousa, Rodolfo V. Rocha, Renato M. Monaro, Alfeu J. Sguarezi Filho https://creativecommons.org/licenses/by/4.0
SiC-Based Half-Bridge Converter: Impact of Gate Resistance on Switching Behavior and Loss Estimation
This study explores the behavior of SiC MOSFETs in a half-bridge converter, emphasizing simulation and experimental validation under both ZVS and non-ZVS conditions. Fast switching and high efficiency make SiC attractive, but parasitic-induced oscillations and EMC require careful design. The influence of gate resistance on switching dynamics and loss mechanisms is analyzed, showing that higher gate resistance reduces oscillations but increases switching losses. For estimating the MOSFET dissipated power, traditional current sensing with current probes or shunt resistors introduces parasitic elements that affect the transistor switching and compromise the instantaneous power measurements. As a result, alternative methods were employed for loss estimation in high-frequency SiC converters. Results demonstrate that increasing gate resistance from 3 Ω to 30 Ω reduces oscillation amplitude by 41%, while increasing switching losses by 53.8%. These findings support gate-drive optimization in SiC-based converters.
Copyright (c) 2026 João J. F. Evangelista Filho, Robson Mayer, José Antenor Pomilio https://creativecommons.org/licenses/by/4.0
Design Methodology for Coupled Inductors Aimed at Reducing Leakage Inductance, Proximity Effect, and Electromagnetic Interference in Quasi-Resonant Flyback LED Drivers
This paper presents a comprehensive study on the influence of winding geometry on leakage inductance and proximity effect losses in coupled inductors applied to quasi-resonant flyback converters for LED drivers. Eleven coupled inductors were designed using the same PQ3220 core, varying the number of layers, interleaving level, and wiring geometry to evaluate their impact on performance. The leakage inductance of each inductor was calculated analytically and measured experimentally, showing strong correlation and validating the analytical method. Additionally, proximity effect losses were estimated through simulations based on winding temperature measurements, allowing the extraction of the AC resistance and proximity factor for each design. The experimental setup involved a 60 W quasi-resonant flyback LED driver operating at around 50 V output, where voltage spikes on the MOSFET, system efficiency, and critical component temperatures were analyzed. Results show that increasing the interleaving level significantly reduces leakage inductance, proximity losses, and electromagnetic emissions, leading to improved efficiency, lower thermal stress, and facilitated regulatory compliance. This study highlights the importance of magnetic design in achieving high-performance LED drivers and provides practical guidelines for minimizing parasitic effects in coupled inductors without increasing component count.
Copyright (c) 2026 João R. C. Amado, Kalyl S. A. Ali, Giulia K. Grassi, Hentony A. Lobo, Renan Rodrigo Duarte, Marco A. D. Costa https://creativecommons.org/licenses/by/4.0
Automatic Power Flow Control Strategy in Hybrid Microgrids: Development and Validation using Controller Hardware-in-the-Loop
Research on hybrid microgrids has attracted significant interest mainly due to the advantages that this topology offers compared to a solely direct current (DC) or alternating current (AC) microgrid. Among these advantages, one of the most frequently mentioned is the increased system reliability, due to the possibility of operating in either islanded mode or grid-connected mode, depending on the need. Additionally, the ability to export power to the AC grid is a valuable application of this type of system. In this context, this paper proposes a new control and management strategy for a hybrid microgrid. The analyzed microgrid consists of a photovoltaic system, energy storage systems, and an emergency power source, as well as DC and AC loads. The interface with the AC side is achieved through an inverter, and the microgrid may or may not be connected to the external grid. The proposed strategy emphasizes the management of all subsystems, as well as the control of operations in both grid-connected and islanded modes. The system was implemented using Controller Hardware-in-the-Loop (C-HIL). The results demonstrated that the proposed strategy enabled effective microgrid management, particularly regarding the proper coordination of the batteries through SOC equalization and the maintenance of each operational state of the microgrid.
Copyright (c) 2026 Danillo B. Rodrigues, Marcus E. T. Souza Junior, Beatriz C. Moura, Érico C. Guimarães , Gabriel M. Bernardes, Ênio C. Resende, Pedro J. S. Neto, Gustavo Brito de Lima, Luiz C. G. Freitas https://creativecommons.org/licenses/by/4.0
An Optimized Hybrid FOPID+RMRAC Control Architecture for Grid-tied Inverters with LCL Filters
This paper presents a novel hybrid control architecture for grid-tied inverters with an LCL filter, combining a fractional-order proportional-integral-derivative controller, dedicated to reference tracking, and a robust model reference adaptive controller, employed for active rejection of grid disturbances. A systematic tuning procedure using the puma optimizer is provided to tune all eleven parameters of the composed control algorithm. Experimental results, performed on a TMS320F28335 Delfino microcontroller equipped in a laboratory prototype, corroborate the simulation findings, presenting fast current tracking and disturbance rejection, with low settling time and total harmonic distortion below the limits established by the IEEE 1547 standard, whose mean between the three-phases is 2.55% in steady state.
Copyright (c) 2026 Cairo T. G. B. Oliveira, Wagner B. da Silveira, Paulo Jefferson Dias de Oliveira Evald https://creativecommons.org/licenses/by/4.0
Analysis and design of a load-independent class-E LCL resonant converter
This work brings in a load-independent Class-E LCL resonant converter. The intertwined soft-switching and load-independent functions in resonant topologies require high mathematical effort and leads to trade-off designing characteristics related to the operating frequency, output power and load range. Therefore, this paper shows the exact analysis for the Class-E LCL converter by axiomatically dealing with the second, third and fourth-order polynomials. In addition, a design method is proposed based on the implicit equations while considering the soft-switching and load-independence features. The measured built prototype operates at 1.2 MHz, which outperforms most of the state-of-the-art compared converters by x 1.2, while maintaining comparable output power and efficiency (92 %).
Copyright (c) 2026 Lucas S. Mendonça, Valmir de Oliveira, Guilherme S. Simeão, Fábio E. Bisogno https://creativecommons.org/licenses/by/4.0
Modeling and Validation of Junction Temperature Estimation in High-Power SiC MOSFET Inverters for Electric Vehicle Applications
The growing concern with reducing CO2 emissions and the demand for sustainable mobility have promoted the adoption of electric vehicles and the use of wide bandgap semiconductors. Thermal management for semiconductor devices is crucial to ensure reliability and efficiency, with junction temperature being a key variable that cannot be directly measured during operation. In this context, this paper proposes a method for junction temperature estimation of SiC MOSFET devices applied to electric traction inverters. A Luenberger state observer is applied to estimate the junction temperature from accessible variables such as ambient temperature, heat sink temperature, and calculated power losses. The method is formulated in a state-space representation, verified through simulations, and validated using an experimental setup, consisting of a single-phase full-bridge inverter. Infrared thermal imaging and physical sensors were employed to compare estimated and measured values. The results demonstrated high accuracy and fast dynamic response of the proposed observer, confirming its robustness and applicability for embedded thermal monitoring in power converters.
Copyright (c) 2026 Leonardo R. Willers, Paulo Henrique Alves da Silva e Silva, Lucas R. Rocha, Rodrigo Padilha Vieira https://creativecommons.org/licenses/by/4.0
Modeling and Control of a Bipolar DC-DC Boost Converter for Bipolar DC Microgrids
Bipolar direct current (DC) microgrids have emerged as a promising alternative for efficiently integrating of renewable energy sources. However, these systems are susceptible to voltage imbalance between the positive and negative poles, especially with asymmetric loads. This paper presents the modeling and control of a non-isolated DC–DC Boost converter with a symmetric bipolar output suitable for photovoltaic applications. The proposed topology eliminates issues related to voltage imbalance and leakage currents while providing continuous low-ripple input current, a reduced number of components, simplified operation, and common grounding with the output neutral point. The operating principle, modeling, and control strategy of the converter are discussed, and its performance is validated through simulations and experimental results from a 1500 W prototype. The results demonstrate stable operation under both balanced and unbalanced conditions.
Copyright (c) 2026 Miréli B. Vendruscolo, Ademir Toebe, Everson Mattos, Leandro Michels, António Manuel Santos Spencer Andrade https://creativecommons.org/licenses/by/4.0
Adaptive Control Based on Virtual Plant Applied to Synchronous Buck Converter using LCL Filter for Charging Lithium-Ion Batteries
This paper introduces a virtual plant method as the main contribution, applied independently to two discrete-time adaptive control strategies for a synchronous buck converter used in battery charging: an Adaptive PI Controller (API) and a Model Reference Adaptive Controller (MRAC). The system employs an LCL filter that interfaces the power converter with the batteries. The proposed virtual plant method enhances the transient performance of adaptive systems by pre-tuning the controller gains before the physical connection, enabling automatic gain initialization and mitigating the poor start-up dynamics typical of adaptive control. The API controller performs real-time adaptation of the parameters Kp and Ki, while the MRAC is based on a reduced-order reference model to simplify its design, updating three parameters: θr, θy and θvb. A simplified methodology for designing adaptive controllers is proposed, involving plant simplification and the use of a virtual plant to automate the controller design process. Controller Hardware-in-the-Loop (C-HIL) and experimental results are presented to validate the control approaches. A fixed PI controller is used as a benchmark for comparison with the adaptive control techniques. Quantitative and qualitative analyses are provided using performance indices such as ISE, IAE, ITSE and ITAE.
Copyright (c) 2026 Vinícius D. Rodrigues, Maicon de Miranda, Wagner B. da Silveira, Jonas Roberto Tibola, Lucas G. Scherer, Rodrigo Varella Tambara https://creativecommons.org/licenses/by/4.0
Dynamic Modeling and Experimental Validation of a Non-Isolated Bidirectional DC-DC Converter for Control-Oriented Design
This paper presents the mathematical modeling and control design of a high-power-density bidirectional DC-DC converter topology based on the three-state switching cell (3SSC). The operation stages corresponding to distinct duty cycle intervals are thoroughly analyzed, and state-space techniques are employed to derive small-signal dynamic models for both Buck and Boost modes. These models serve as the foundation for the design of digital compensators using classical frequency-domain control methods, ensuring compliance with predefined performance specifications. To verify the accuracy and applicability of the derived models, a comparative analysis is conducted between simulated and experimental closed-loop responses. The same compensators, designed using the mathematical models, are implemented both in circuit-level simulations and in a 2 kW hardware prototype operating at 200 V in Buck mode and 550 V in Boost mode, with a switching frequency of 20 kHz. The observed agreement in dynamic behavior under both reference and load disturbances validates the proposed models and confirms their suitability for control-oriented applications. This comparative validation approach represents the main contribution of the work, demonstrating that the small-signal plant models faithfully reproduce the real converter dynamics and can be reliably used in the design of digital controllers for bidirectional power conversion systems.
Copyright (c) 2026 Marciel Wenk, Felipe J. Zimann, Robson Mayer, Sérgio Vidal Garcia Oliveira, Alessandro L. Batschauer https://creativecommons.org/licenses/by/4.0
Notch-Filter-Based Control Strategy to Extend Stability Limits of LCL-Filtered Grid-Connected Inverters
The stable connection of energy sources to the grid via LCL-filtered inverters is often constrained by delays introduced by digital implementation and DPWM modulation. This paper proposes a novel notch-filter-based compensation strategy that explicitly mitigates such delays, extending the stability region of the current control system by increasing the critical frequency. In addition, a systematic methodology is introduced for tuning the active damping gain, demonstrating its direct influence on phase margin and robustness - an aspect not systematically addressed in previous studies. Unlike approaches based on auto-tuning or real-time resonance estimation, the proposed method imposes no additional computational burden while significantly expanding the stability limits. Analytical studies, frequency-domain analysis, and experimental validation using a hardware-in-the-loop (HIL) platform confirm that the proposed strategy extends the stable operating region, improves dynamic performance, and reduces harmonic distortion, representing a distinctive contribution to the control of LCL-filtered grid-connected inverters.
Copyright (c) 2026 James N. Silva, Filipe A. da C. Bahia, Andre P. N. Tahim, Darlan Alexandria Fernandes, Fabiano Fragoso Costa https://creativecommons.org/licenses/by/4.0
Integrated Cloud and Hardware-in-the-Loop Framework for IoT-Based Control and Monitoring
This work introduces a Cloud-in-the-Loop approach that combines Internet of Things (IoT) devices with Hardware-in-the-Loop simulation for testing control and monitoring applications. The proposed architecture employs a three-level hierarchical structure: the first level simulates the Battery Energy Storage System and local power flow control on a Digital Sampling Processor microcontroller, the second level uses an ESP32 microcontroller for Controller Area Network (CAN) communication and data transmission to the cloud, and the third level, implemented with an online broker, enables data storage, analysis and commands. A simplified power flow model and a battery model representation are considered to evaluate long-term operation with one year of climate and load data. Two load management strategies were compared: (i) total load shedding at 0% State of Charge, and (ii) hierarchical load disconnection at predefined SOC thresholds. Results showed that the hierarchical strategy increased the average State of Charge by 25.2% (54.66% vs. 43.64%), prevented interruptions to critical loads. The results show that the proposed framework serves as a flexible step before real deployment, since its cloud-based functions remain unaltered while only the physical hardware is replaced. This approach reduces implementation problems and allows the methodology to be extended to various case studies.
Copyright (c) 2026 Diuary Gonçalves, Ives de O. Furtado, Allan F. Cupertino, Heverton Augusto Pereira, Remus Teodorescu https://creativecommons.org/licenses/by/4.0
Quantification Errors Due to Inaccurate Use of Power Factor Definition
This article discusses the anachronism, insufficiency, and imprecision of the formulation and definitions of power factor (PF) in several regulatory texts. For consumer units in distribution networks, analyses are presented of how ANEEL defines this figure of merit. In the case of individual equipment, INMETRO's measurement procedures employ formulas that, depending on the tested device's operating principle, may yield technically erroneous results. For example, the results of LED luminaires, which are supposedly designed to have a high power factor, are analyzed and it is concluded that the solution for the errors in single-phase case is straightforward, and are achieved by using the correct formulation of the power factor, defined as the ratio between active and apparent power, with a sufficiently high sampling rate to capture the possible high-frequency spectral components of the current. Modern digital measuring instruments can easily obtain such quantities and do not incur errors that may arise from using quantities such as distortion factors or fundamental displacement.
Copyright (c) 2026 Jose A. Pomilio, Sigmar M. Deckmann, Jose C. U. Pena, Mateus P. Dias https://creativecommons.org/licenses/by/4.0
Calculation of the equivalent circuit for a plastic film capacitor intended for DC-link application in power electronic converters
Capacitor designs employed in DC-link applications of power electronic converters must minimize equivalent series resistance and parasitic inductance due to the adoption of wide bandgap semiconductors, which enable operation at significantly higher temperatures, voltages, and switching frequencies. The paper focuses on characterizing metallized plastic film capacitors by analyzing the influence of materials, dimensions, and construction features, both of the capacitive element and of the connections and terminals, on parasitic inductance and associated losses, thereby supporting the development of an equivalent circuit model. A comprehensive literature review establishes the theoretical foundation for the analytical formulation, which is then applied to the structural characteristics of the capacitor under investigation to derive the parameters of the equivalent circuit. The calculated values of equivalent series inductance and equivalent series resistance are validated through comparison with measurements obtained from different capacitor models. The results confirm the accuracy of the proposed calculation method, as the observed deviations remain within acceptable limits, considering the inherent variability of raw materials, manufacturing processes, and measurement procedures.
Copyright (c) 2026 Alessandra C. Fragoso, Alessandro L. Batschauer https://creativecommons.org/licenses/by/4.0
Gauss-Newton Method Applied to Impedance Estimation in Grid-Connected Inverters
This work presents a methodology that employs the Gauss–Newton algorithm to perform online impedance estimation for grid-connected inverters. Conventional formulations for this class of problem typically lead to high-order nonlinear systems of equations, often of dimension 8×8. In contrast, the formulation proposed herein recasts the estimation task as a 3×3 least-squares problem, which is then solved via the Gauss–Newton method. To validate the proposed approach, a three-phase grid-connected inverter was adopted as the case study. The control system enforces three distinct active power injection levels into the grid, and the voltage, current, and phase-angle magnitudes at the point of common coupling are measured and used as inputs to the impedance estimation algorithm. Real-time validation was carried out to assess the performance of the method. The results confirm the feasibility of the proposed formulation and indicate that the approach substantially reduces the computational burden of embedded DSP-based algorithms for online grid impedance estimation.
Copyright (c) 2026 Jefferson R. P. de Assis, Darlan A. Fernandes , Maurício B. de R. Corrêa, Alfeu J. Sguarezi Filho, Fabiano F. Costa, Edison R. C. da Silva https://creativecommons.org/licenses/by/4.0
Feasibility Implementation Analysis of the Parks-McClellan Algorithm in Capacitor Voltage Active Damping
This paper presents an analysis of the computational implementation of capacitor-voltage-based active damping (CVAD) for mitigating the resonance of LCL filters in power electronic converters based on Parks–McClellan (PM) FIR differentiator. The proposed approach relies on capacitor voltage feedback, eliminating the need for additional current sensors while ensuring both active damping and synchronization. The FIR differentiator, designed with the PM algorithm, emulates the derivative with low noise amplification and minimal phase delay, enabling effective resonance attenuation over a wide frequency range. The study addresses the implementation of the algorithm and provides a critical review of its applicability in conventional single-core and dual-core digital signal controllers, such as the TMS320F28335 and TMS320F28379D. Experimental validation on a single-phase grid-connected inverter demonstrates the effectiveness of the method in suppressing LCL resonance, highlighting its processing rate, feasibility for different filter orders, and practical viability in commercially available Digital Signal Controllers (DSCs) for both academic and industrial applications.
Copyright (c) 2026 José de A. Olímpio Filho, Luis de O. Arenas, Paulo Fernando Silva, Lucas C. Souza, Fernando P. Marafão, Tiago D. C. Busarello, Helmo K. M. Parede https://creativecommons.org/licenses/by/4.0
Efficiency Optimization of a Dual Active Bridge Converter with a Variable Inductor for Battery Charging Applications
This paper investigates the efficiency improvements achieved by using a Variable Inductor (VI) in a Dual Active Bridge (DAB) converter for battery charging applications. The introduction of the VI adds a degree of freedom to conventional Phase-Shift Modulation (PSM), which extends the soft-switching range under light-load conditions and reduces reactive power under high load conditions. However, an optimal combination of power transfer inductance (LDAB) and phase-shift (PS) exists that yields maximum efficiency for each output power (Po), and conversion ratio d. To validate this, a 600 W DAB converter prototype was experimentally developed. The efficiency results obtained from a sweep of LDAB and PS were compared against those of a fixed-inductance DAB (FI-DAB). The experimental results demonstrate the superior performance of the proposed VI-DAB converter under both high and low load conditions.
Copyright (c) 2026 Conrado G. Marques, João P. S. Cipriani, Leandro Roggia, Marina S. Perdigão, Jonas R. Tibola, Álysson Raniere Seidel https://creativecommons.org/licenses/by/4.0
Design, FEA-Based Physical Insights, and Experimental Verification of a Planar Transformer for Two-Switch Flyback Converters
Parasitic parameters in high-frequency transformers directly impact losses, electromagnetic interference (EMI), and voltage/current stresses in power converters. This paper presents a comparative analysis and optimization of planar transformers (PT) applied to a two-switch Flyback (TSF) converter. The investigation focuses on balancing leakage inductance, AC resistance, and parasitic capacitances through different PCB winding arrangements using multiphysics Finite Element Analysis (FEA). By employing a structured analysis that correlates electromagnetic and thermal modeling with experimental validation, this work demonstrates how layer alignment and interleaving mitigate proximity effects and drastically reduce ringing in semiconductor switches. The results show that the optimized configuration achieved an 80% reduction in leakage inductance and a 57% reduction in AC resistance compared to conventional designs, resulting in an efficiency of 89.2% and a significant decrease in thermal stress. The study provides evidence-based design guidelines for mitigating parasitic effects in high-power-density converters.
Copyright (c) 2026 Naelton O. de Souza, Djonny Weinzierl, Maicon W. M. de Carvalho, Rodrigo Heinrich, Sergio V. G. Oliveira https://creativecommons.org/licenses/by/4.0
Online SoC Balancing Strategy for Distributed Single-Stage MMC-Based BESS
This paper proposes an online state-of-charge (SoC) balancing strategy for a distributed single-stage Modular Multilevel Converter-based Battery Energy Storage System (MMC-BESS). The main contribution is the development of a low-complexity sorting-based selection algorithm integrated into the smart-battery concept, enabling real-time energy redistribution among submodules without requiring additional auxiliary balancing circuits. The proposed method operates jointly with a phase-disposition pulse width modulation (PD-PWM) strategy and is coordinated with conventional grid current control in the synchronous reference frame and circulating current suppression control, thereby ensuring stable converter operation. The complete three-phase MMC-BESS, composed of 18 submodules per arm, was modeled and validated using PSCAD/EMTDC simulations. The performance of the proposed balancing algorithm was evaluated under multiple operating conditions, including active power injection, active power absorption, and reactive power support. Simulation results demonstrate effective SoC equalization across all submodules while maintaining high-quality AC voltage and current waveforms and while ensuring suppression of internal circulating currents. The simulation results confirm the robustness, scalability, and practical applicability of the proposed control strategy, highlighting its potential for improving reliability, extending battery lifetime, and enabling MMC-based BESS to provide ancillary services and support large-scale integration of renewable energy sources.
Copyright (c) 2026 Juan A. P. Garay, Pedro M. Almeida, Pedro G. Barbosa https://creativecommons.org/licenses/by/4.0
Real-World SoC Estimation for Lithium-Ion Batteries in Electric Buses: Sampling Resolution and Machine Learning Efficiencys
Accurate State of Charge (SoC) estimation is essential for safe and efficient lithium-ion battery operation in electric mobility. Although machine learning methods achieve high predictive capability, many studies rely on laboratory cycling data and overlook deployment constraints such as latency and embedded hardware. This paper presents a deployment-oriented evaluation of data-driven SoC estimation using large-scale operational data from a battery electric bus. The dataset includes more than 4.3 million field measurements of current, voltage, temperature, and SoC collected under realistic driving conditions. Five models are compared: Random Forest, LightGBM, XGBoost, Temporal Convolutional Networks (TCN), and Gated Recurrent Unit (GRU) networks. Models are evaluated across sampling intervals from 30 s to 210 s and multiple training-data fractions, considering accuracy, training time, and inference latency. Results show that temporal resolution strongly affects the accuracy-efficiency trade-off. The best configuration, LightGBM at 180 s using 75 % of training data, achieved a test MAE of 6.338, RMSE of 8.495, and median inference latency of 1.10 ms. Compared with the Random Forest baseline at 30 s, it reduced MAE by 34.4 %, RMSE by 35.6 %, and latency by 97.6 %, supporting efficient real-time battery management system deployment.
Copyright (c) 2026 Johanna P. Orellana-Iñiguez, Waldyr L. R. Gallo, Madson C. de Almeida https://creativecommons.org/licenses/by/4.0
A Simplified Approach for Beat Frequency Oscillation Analysis in DC Microgrids
This paper investigates beat frequency oscillations in dc microgrids, which occur due to switching frequency mismatches between cascaded converters. These oscillations can be aggravated by non-synchronized sampling in control systems, leading to stability and performance issues. The study introduces a simplified transfer function model that relates beat frequency disturbances to output voltage oscillations. Unlike previous methods, this approach allows for systematic analysis using Bode diagrams, providing a clear understanding of the mechanisms behind these disturbances. The analysis evaluates three configurations—ranging from a baseline setup to one including EMI filters and long cable feeders—using a 4.75 kW experimental prototype. The proposed model demonstrates high accuracy, with a maximum magnitude deviation of less than 2 dB up to 20 kHz. Furthermore, the model successfully predicts a critical resonance at 19.4 kHz, which amplifies oscillations by 8 V peak-to-peak. The results confirm that beat-frequency gain remains near 0 dB for frequencies below 1 kHz, while high-frequency attenuation exceeds 40 dB. Ultimately, this work offers a computationally efficient tool for stability assessment and effective filter parameter tuning in dc microgrids.
Copyright (c) 2026 Debora P. Damasceno, José Carlos U. Peña, Mateus P. Dias, Danilo Iglesias Brandao, José A. Pomílio https://creativecommons.org/licenses/by/4.0
Grid-Forming Control in HVDC-based Offshore Wind Farms: A Review of Recent Worldwide Breakthroughs and Challenges for the Brazilian Scenario
Offshore wind power generation has become established as a technically attractive alternative for coastal regions. In this scenario, the migration from grid-following control strategies to grid-forming approaches emerges as a demand of the power system to encapsulate grid support functionalities within the wind energy conversion systems (WECS), consolidating grid-forming as one of the main research frontiers. This work provides a review on recent control strategies for high-voltage direct current (HVDC) transmission-based offshore wind farms, exploring the innovative breakthroughs and explaining how these approaches enable voltage and frequency regulation, black start capability, and improved dynamic performance. The interplay between grid-formation capability, system inertia emulation, and fault ride-through capability is also examined. By bridging the gap between academic advancements and real-world offshore deployment, this study outlines future pathways toward inverter-dominated offshore WECS. Additionally, this work also offers insights into the challenges associated with integrating grid-forming inverters into offshore WECS, with particular consideration given to the Brazilian context.
Copyright (c) 2026 Paulo J. D. de O. Evald, Hugo N. Raffi, Lenon Schmitz , Jéssika M. de Andrade, Romero Leandro Andersen, Telles B. Lazzarin https://creativecommons.org/licenses/by/4.0