{"title":"Improved Direct Power Control of T-Type Rectifiers With Parameter Robustness Feedforward Compensation for DC-Bus Voltage Ripple Suppression Under Unbalanced Grid Conditions","authors":"Yi-Hung Liao;Jia-Sheng Liu;Pu-Yi Huang;Ping-Ju Chen","doi":"10.1109/OJIES.2025.3549475","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3549475","url":null,"abstract":"In a three-phase three-level ac/dc converter, the T-type rectifier features high efficiency and lower power switch stress, and it allows the dc-side voltage to serve as two independent output voltage sources. In practical applications, the operation of the T-type rectifier under unbalanced three-phase grid conditions must be considered. This article establishes an improved direct power control structure based on extended power theory under unbalanced grid conditions to achieve distortion-free current for the T-type rectifier. Additionally, a feedforward virtual capacitor power compensation is created to eliminate the output voltage ripples caused by the ripple power of the rectifier inductance under the unbalanced three-phase grid. The controller design of the improved direct power control and the choice of the virtual capacitor are analyzed. Furthermore, the proposed method regulates the neutral point voltage of the T-type rectifier, eliminates neutral point current disturbances, and provides a stable and accurate dc output voltage, ensuring high quality power supply. The proposed strategy does not require a phase-locked loop or ac-side system parameters, resulting in excellent dynamic performance and robustness against parameter mismatches. Finally, the effectiveness and feasibility of the proposed control strategy are verified through simulation results and the implementation of a 2.4 kW three-phase T-type rectifier.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"429-444"},"PeriodicalIF":5.2,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10918756","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New Bidirectional Isolated Three-Phase DC–DC Converter With Parallel-to-Serial Configuration for Energy Applications","authors":"Jorge Jiménez-Giménez;Antonio Lázaro;Álvar Mayor;Jaime López-López;Andrés Barrado","doi":"10.1109/OJIES.2025.3548842","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3548842","url":null,"abstract":"This article presents a set of bidirectional dc–dc power converter solutions for high-voltage, high-power applications using magnetic and semiconductor devices that need to handle a small fraction of the rated power and voltage. The elements are integrated in an interleaved operation, which results in the generation of a low rms and pseudosine phase current. All these features result in a topology with a high level of efficiency, maintaining soft-switching over the entire operating range. Steady-state equations and simulation results are presented and then experimentally validated with a 25 kW prototype converter. Finally, it is verified that the solution is suitable for the needs of the proposed dc-microgrid scenario, that includes hydrogen production and an EV-charger, using solar PV-panels and battery energy storage systems as energy sources.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"459-477"},"PeriodicalIF":5.2,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10916738","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Roberto Martín López;Sergio de López Diz;Alessandro Faro;Emilio José Bueno Peña;Alessandro Lidozzi
{"title":"Grid-Forming Controller for Multi DC/AC Converter Topology Supplying 25 kVAC Single-Phase Railway Catenary From 3 kVDC","authors":"Roberto Martín López;Sergio de López Diz;Alessandro Faro;Emilio José Bueno Peña;Alessandro Lidozzi","doi":"10.1109/OJIES.2025.3548456","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3548456","url":null,"abstract":"One of the primary challenges associated with single-phase AC railway electrification is the unbalance created within the three-phase supply grid. This problem does not arise in DC electrification systems. The aim of this article is to introduce a novel Grid-Forming control strategy, which applied to a power electronics based topology allows the generation of an AC catenary from the DC catenary. Focusing on the capabilities of the control algorithm, the system is presented as a fully scalable solution employing multiple grid-forming DC/AC converters. These converters use power control loops based on the Virtual Synchronous Machine concept, adapted to single-phase operation. A key advantage of this approach is that all converters within the system contribute to supporting both voltage and frequency stability. In addition, the implementation does not require a higher-level controller or communication system. Through an appropriate power control design, the power supplied by each converter, relative to the total load demand, can be determined.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"445-458"},"PeriodicalIF":5.2,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10914004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Otto—Design and Control of an 8-DoF SEA-Driven Quadrupedal Robot","authors":"Antonello Scaldaferri;Simone Tolomei;Francesco Iotti;Paolo Gambino;Michele Pierallini;Franco Angelini;Manolo Garabini","doi":"10.1109/OJIES.2025.3567112","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3567112","url":null,"abstract":"This article presents the mechanical design of Otto, a lightweight 8-degrees-of-freedom (8-DoF) quadrupedal robot employing series elastic actuators, and a training framework for learning locomotion control policies in simulation using reinforcement learning (RL). Otto's design differs from typical 12-DoF quadrupeds by lacking hip adduction–abduction DoF. This reduces the robot's cost and weight and increases complexity for tasks involving base rotation and angular twist following. The elastic elements at the joints improve compliance, energy efficiency, safety, and stability, increase robustness, and reduce damage to robot hardware components. Our locomotion control approach leverages RL to optimize policies in simulation, allowing stable and efficient movement despite mechanical constraints, i.e., an 8-DoF quadrupedal robot. Through extensive simulation training, leveraging highly parallel Graphics Processing Unit (GPU)-accelerated robotic simulators, we ensure the policy is well-suited for deployment in real-world scenarios, where accurate motion control is critical for performance. The trained policy is then transferred to the physical robot platform. We demonstrate its effectiveness in various tasks and real-life scenarios with varying payloads and terrains, and compare it with a state-of-the-art model-based method. The results show that Otto, equipped with our RL-based locomotion control, achieves robust performance, compensating for the reality gap and managing the reduced DoF available in Otto.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"820-839"},"PeriodicalIF":5.2,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10988638","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improving Speed Regulation of a Permanent Magnet Synchronous Motor Using Modified Model Predictive Control With an Adaptive Second-Order Disturbance Observer","authors":"Ton Hoang Nguyen;Ty Trung Nguyen;Jae Wook Jeon","doi":"10.1109/OJIES.2025.3547767","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3547767","url":null,"abstract":"In this study, we propose a modified model predictive control (MMPC) approach combined with an adaptive second-order disturbance observer (ASDO) for efficient speed control of permanent magnet synchronous motors in the presence of unknown disturbances, such as system parameter variations and external load torque. The MMPC incorporates feedforward reference compensation (FFRC) and a posterior constraint compensation (PCC) technique. When the motor operates on a nonconstant velocity profile, the FFRC technique reduces the tracking delay associated with conventional MPC methods. In addition, the PCC technique addresses control signal constraints under a step velocity profile without requiring the solution of complex optimization problems at each time step, thereby reducing the computational effort for the controller. Furthermore, the ASDO utilizes a second-order disturbance observer to enhance the robustness of the MMPC. An adaptive observer bandwidth algorithm is proposed to minimize random noise and current ripple. The performance of the proposed methods was evaluated by applying them to an industrial motor drive, confirming their validity and practicality in real-world operations.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"415-428"},"PeriodicalIF":5.2,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10909597","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143667294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Manuel Martínez-Gómez;Marcos E. Orchard;Serhiy Bozhko;Patrick Wheeler;Claudio Burgos-Mellado
{"title":"Distributed Control Scheme for the Coordination of Interlinking Converters in Islanded Hybrid AC/DC Multi-Microgrids","authors":"Manuel Martínez-Gómez;Marcos E. Orchard;Serhiy Bozhko;Patrick Wheeler;Claudio Burgos-Mellado","doi":"10.1109/OJIES.2025.3545632","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3545632","url":null,"abstract":"Multiple interconnected ac and dc microgrids (MGs) are being studied by academia and industry because of their benefits despite their operational challenges. Coordinating distributed generators (DGs) is complex, so communication-based controllers are proliferating in the literature. Then, this work proposes a distributed control strategy for islanded ac/dc multi-MGs interconnected by interlinking converters (ILCs). The proposed scheme is implemented in the ILCs and consists of distributed controllers that equalize global generation costs, allowing secondary control in each MG. Control actions that safeguard the saturated operation of MGs and ILCs are included in the control designs. The simultaneous operation with multiple objectives is possible due to adjusting control parameters according to a prioritization criterion. Experiments are conducted through an extensive simulated environment. The results show the proposed multiobjective controllers could maintain global optimal costs during normal operation while not overloading DGs, ILCs, subgrids, and clusters of ILCs. Furthermore, the strategy may reduce operational costs in the long term by protecting the lifetime of critical MG components. Desynchronization of incremental costs is enforced at 15% at most under demanding conditions. Also, it is possible to operate against considerable (<inline-formula><tex-math>$>$</tex-math></inline-formula>250 [ms]) time delays in the tests.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"358-379"},"PeriodicalIF":5.2,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10909984","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomasz Święchowicz;Sebastian Styński;Krzysztof Kulikowski
{"title":"Reduced-Delay Sigma-Delta Filter for Accurate Current Measurement in PWM VSCs","authors":"Tomasz Święchowicz;Sebastian Styński;Krzysztof Kulikowski","doi":"10.1109/OJIES.2025.3546820","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3546820","url":null,"abstract":"The popularity of sigma-delta measurement (SDM) in power electronics is increasing due to its high accuracy but is hampered by the significant measurement delay it introduces. This delay is further increased if the SDM's digital filter is designed to attenuate not only the quantization noise but also the pulsewidth modulation (PWM)-related harmonics. The main objective of this article is to improve the SDM methodology by adding and verifying a new digital filter, named the TSS filter, which reduces measurement delay while remaining robust against the presence of PWM ripple. Given the limited amount of published information on SDM accuracy in PWM voltage-source converters (VSCs), the secondary objective of this article is to experimentally compare it against regular sampled measurement (RSM) on a dedicated platform. To show that the resulting inaccuracies are inherent to RSM rather than stemming from poor converter design, an analysis of measurement error sources in PWM VSCs is conducted.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"345-357"},"PeriodicalIF":5.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10908654","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cesar Limones;Nimrod Vázquez;Ricardo Femat;Leonel Estrada;Jeziel Vázquez;Claudia Hernandez;Angel de Castro;Joaquín Vaquero
{"title":"Single-Phase Grid-Connected Inverter With Predictive Control Cost Function for Leakage Current Mitigation and FAS Model","authors":"Cesar Limones;Nimrod Vázquez;Ricardo Femat;Leonel Estrada;Jeziel Vázquez;Claudia Hernandez;Angel de Castro;Joaquín Vaquero","doi":"10.1109/OJIES.2025.3566582","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3566582","url":null,"abstract":"Leakage current is one of the main issues for transformerless grid-connected photovoltaic inverters, and its reduction is a primary focus of various studies reported in the literature. This article proposes and validates a finite control set model predictive controller with a novel cost function to mitigate leakage current in a single-phase full-bridge (FB) grid-connected inverter with an <italic>LCL</i> filter, making no modifications to the traditional FB topology and without adding any extra components. Furthermore, mathematical modeling is based on the fully actuated system model, allowing a reduction in the number of variables sensed during implementation, resulting in only grid current and voltage being measured.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"764-774"},"PeriodicalIF":5.2,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10982184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143949191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Grid Forming Converters for Low Inertia Systems-Capabilities and Limitations: A Critical Review","authors":"Qusay Salem;Bayan Bany Fawaz;Rafat Aljarrah;Mazaher Karimi","doi":"10.1109/OJIES.2025.3566213","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3566213","url":null,"abstract":"The rapid integration of renewable energy sources into the power grid has resulted in the high utilization of power-electronics devices and operating power systems where inverter-based resources are dominated. Such a transition has led to a reduction of inertia and system strength. In recent research, grid-forming converters (GFM) are introduced and developed to alleviate the grid-following converter (GFL) functionalities and to address the limitations concerning grid support capability, stability, and synchronization issues. However, the efficacy of GFM technology is still under investigation, and the level at which GFM converters can replace traditional GFLs is still under question. This article aims to bridge the gap in literature by revisiting the up-to-date research on the capabilities and the limitations of the proposed GFM converters compared to the traditionally utilized GFL converters, allowing a better understanding of the current status and future requirements. This includes the GFM converter's topologies and their performance for small- and large-signal stability issues, the GFM converters' ability to enhance grid synchronization, and transient stability performances. Furthermore, the challenges and limitations of the dynamic behavior of GFM converters from the point of view of fault ride through (FRT) capability, including grid codes and FRT requirements, FRT methods of GFM converters, postfault behavior, and open research directions, are also comprehensively reviewed. Finally, this article has been concluded by highlighting the main findings, considerations, and future recommendations.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"775-801"},"PeriodicalIF":5.2,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10981620","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phanit Sok;Sung-Geun Song;Guangxu Zhou;Feel-Soon Kang
{"title":"Improving Surge Voltage and Power Loss of the MOV-MOV-C Approach for Low-Scale DC Solid-State Circuit Breaker Applications","authors":"Phanit Sok;Sung-Geun Song;Guangxu Zhou;Feel-Soon Kang","doi":"10.1109/OJIES.2025.3566146","DOIUrl":"https://doi.org/10.1109/OJIES.2025.3566146","url":null,"abstract":"The dc solid-state circuit breaker (SSCB) is commonly used to protect sensitive equipment and enhance system stability by quickly interrupting fault currents, thereby increasing overall safety. The double metal oxide varistors (MOVs) and the single capacitors are the snubber circuit topologies represented by MOV-MOV-C that have been successfully demonstrated through design and experimentation, effectively suppressing high-frequency oscillations caused by the capacitance of the MOV and blocking low-frequency harmonics introduced by the RC snubber. However, previous research highlights critical areas for improvement, particularly in reducing surge voltage across the main breaker switch, minimizing power loss in on-state normal operation, and discussing the overall design cost in low-scale applications. This article analyzes and compares power loss between different types of semiconductor switches to optimize and minimize it. The surge voltage also improves from the traditional MOV-MOV-C into a proposed enhancement incorporating a new MOV featuring a lower dc-rated and maximum clamping voltage aimed at optimizing surge voltage protection, represented by a Triple-MOV-C snubber circuit. A cost model for critical components was also developed to discuss the total design based on a low-scale dc SSCB application of both snubber circuits and validated through the graph. Finally, the validation of power loss and surge voltage improvements was conducted through small-scale experiments.","PeriodicalId":52675,"journal":{"name":"IEEE Open Journal of the Industrial Electronics Society","volume":"6 ","pages":"708-721"},"PeriodicalIF":5.2,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10981697","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}