Guangdi Li;Qizhen Wu;Abhishek Kumar;Bowen Zhou;Bikash Sah;Ramesh C. Bansal;Yan Deng
{"title":"Three-Level Circulant Modulation With Submodule-Capacitor Voltage Natural-Balance Capability for Bidirectional Modular DC–DC Converter","authors":"Guangdi Li;Qizhen Wu;Abhishek Kumar;Bowen Zhou;Bikash Sah;Ramesh C. Bansal;Yan Deng","doi":"10.1109/JESTIE.2025.3647033","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3647033","url":null,"abstract":"A three-level duty-cycle phase-shift circulant modulation with submodule (SM) voltage natural balancing for a bidirectional modular dc–dc converter is proposed in this article. Compared with the conventional single-phase-shift circulant modulation to achieve capacitor voltage balance in SMs, the proposed duty-cycle phase-shift circulant modulation method offers advantages, such as lower current stress and voltage change rate (<italic>dv/dt</i>) along with voltage natural balancing. Furthermore, circulant modulation enables a highly flexible voltage conversion ratio while inherently achieving natural balancing of SM-capacitor voltages, without additional feedback control. In addition, the low switching frequency operation of SMs, combined with a high operational frequency, facilitates a significant reduction in the size of passive components, thereby enhancing system efficiency and compactness. This article presents the working principle and theoretical analysis of the converter in detail, followed by experimental validation based on a hardware prototype built and tested in the laboratory.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"522-532"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148513553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qianjin Zhang;Hongjie An;Lin Zhang;Peng Yu;Sucheng Liu;Xiaodong Liu
{"title":"Enhanced Lyapunov-Based Control for Inverter Systems in Series-Compensated Transmission Networks","authors":"Qianjin Zhang;Hongjie An;Lin Zhang;Peng Yu;Sucheng Liu;Xiaodong Liu","doi":"10.1109/JESTIE.2026.3653214","DOIUrl":"https://doi.org/10.1109/JESTIE.2026.3653214","url":null,"abstract":"Series capacitor compensation is widely employed in transmission lines to compensate for grid impedance and enhance the transmission capability of renewable power. However, it can adversely affect inverter current control and potentially induce system oscillations. In conventional linear control theory, lead compensation can be applied to increase the phase margin and address the instability issues. Nevertheless, the compensation typically requires multiple rounds of offline adjustments and relies heavily on accurate system modeling and precise calculation of compensation frequencies, making it difficult to achieve online optimization control. In recent years, advanced control strategies, such as those based on the Lyapunov function, have been significantly developed. However, existing control strategies cannot be directly applied to inverter systems with series compensation, as they do not account for the effects of grid impedance and series capacitors. To bridge this gap, this article proposes a current control scheme based on the Lyapunov direct method to mitigate the impact of series compensation on current control stability. A Lyapunov function that ensures global stability is derived and implemented. The perturbation gains are designed using root locus analysis to improve both static and dynamic performance. Finally, the effectiveness of the proposed control strategy is validated through experiments.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"581-590"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148513615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Series Voltage Injection Based Dual-Port Triple Active Bridge Converter With Reduced Link Current Stress and Enhanced Performances for Wide Operating Ranges","authors":"Silpashree Sahu;Dipankar De;Alberto Castellazzi","doi":"10.1109/JESTIE.2025.3642306","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3642306","url":null,"abstract":"This article introduces a novel series voltage injection-based dual-port triple active bridge converter aimed at reducing the ac link current stress of the converter. This reduction in link current stress is achieved by incorporating an auxiliary series voltage injection from a third bridge. The proposed converter has enhanced power transfer capability with input and output voltage variation compared to conventional dual active bridge converters. Second, it exhibits lower link current stress, leading to reduced switch stress and improved efficiency due to lower losses. Despite the increase in component count, the overall cost of the converter is reduced. Third, the design of the proposed converter allows for reduced link inductance for a given peak current in magnetic components. This is an improvement over conventional designs, even when advanced modulation/optimization is applied for applications with wide ranges of operating points. A detailed cost-efficiency comparison shows that the proposed solution is not only efficient, but also economical compared to the conventional solution, irrespective of the increased components. The article provides a comprehensive analysis that includes soft-switching behavior, mathematical modeling across various operating modes, and loss calculation of the proposed configuration. Detailed performance comparison with existing configurations employing various modulation and optimization schemes shows the superiority of the proposed solution. Finally, the proposed concept is verified through simulation studies and through a scaled-down experimental prototype.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"557-569"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148513819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Reinforcement Learning-Based Control of Voltage-Forming Grid Inverters With Arbitrary Loads","authors":"Daniel Weber;Jarren Lange;Oliver Wallscheid","doi":"10.1109/JESTIE.2026.3654784","DOIUrl":"https://doi.org/10.1109/JESTIE.2026.3654784","url":null,"abstract":"Reinforcement learning-based control allows a model-free, self-adaptive control approach with the possibility of nonlinear and complex control, which is desired for inverter-based energy grids, but faces safety-related challenges. To avoid overcurrents and overvoltages in a control task on component level, a safeguard is presented, which is capable of dealing with arbitrary loads without the need of a priori knowledge during the training process of the reinforcement learning-based controller. The control plant is a three-phase, four-wire, three-level 250 kVA-capable inverter with an <italic>LC</i>-filter. After 6 min of training, a reinforcement learning controller achieves a normalized mean absolute error (w.r.t. the reference voltage amplitude) in a voltage control task of 0.33% in steady state. During a transient loadstep of 1 kA within 1 ms, corresponding to a current change of 200 % of the rated current, the reinforcement learning controller is capable of safely and stably tracking the setpoint. In a comparison to various model-based, expert-driven controllers, in particular a cascaded PI controller, a predictive dead-beat controller and a combination of both, the reinforcement learning controller shows comparable or better results, both in steady state as well as in transient behavior and enables a highly automated controller design toolchain with minimal human effort, without prior system knowledge and without simulative pretraining.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"545-556"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11355760","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148509541","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":"Double-Nonlinear-Disturbance-Observer-Based Funnel Control for Permanent-Magnet Synchronous Motors","authors":"Shubo Wang;Guanfeng Zhufu;Haoran He","doi":"10.1109/JESTIE.2025.3647268","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3647268","url":null,"abstract":"This article proposes an interconnected double nonlinear disturbance observer (DNDO)-based funnel controller for noncascade control structure permanent-magnet synchronous motors. In a noncascade control structure, the disturbance in the current loop is not matched, and it has a negative impact on the system performance and stability. To overcome this problem, an interconnected DNDO is designed to deal with the mismatch disturbance. Then, a novel nonlinear funnel error surface is proposed, which is based on improved fixed-time performance functions that ensure tracking error evolution. The DNDO incorporates with the funnel error surface to design a funnel controller that improves the tracking performance of the system. In addition, a current constraint scheme for the noncascade controller is designed. Then, the stability of the closed system under the presented control strategy is guaranteed by the Lyapunov stability theory. Finally, the effectiveness and practicability of the developed method is validated by using the comparative simulations and experiments.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"440-450"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148509542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amit Gupta;P. C. Sekhar;Merkebu Z. Degefa;Kjell Ljøkelsøy;Salvatore D’Arco
{"title":"A Unified Controller for Interconnection of Heterogeneous, Multi-DG Mini/Microgrids With Varying Dynamic Characteristics","authors":"Amit Gupta;P. C. Sekhar;Merkebu Z. Degefa;Kjell Ljøkelsøy;Salvatore D’Arco","doi":"10.1109/JESTIE.2025.3642906","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3642906","url":null,"abstract":"Realizing the necessity and benefits of integrated operation of multiple microgrids (MGs), this article proposes a unified controller for the interconnection of MGs energized with a variety of distributed generators (DGs), including both rotating machine-based and inverter-based interfacing systems. The developed controller adopts an embedded loop approach that corrects the frequency and phase errors adaptively, thereby eliminating the need for multiloop sequential controllers, and accelerating the alignment of the phase and frequency of incoming MG with that of the existing/reference MG system. The controller tuning process is simplified with the incorporation of rate of change of frequency and an aggregated modeling approach in the design, which enhanced the flexibility and robustness. Care has been taken such that the developed philosophy shall be generic, so that it can be scalable and can be applied to the interconnection of any two MGs, irrespective of the type and number of DGs within each MG, and their time-varying responses. The performance of the developed controller is verified through various numerical simulations and is validated through experiments on a power-hardware-in-loop-based test bed for seamless interconnection, undisturbed power deliveries, and stable post-interconnection operations.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"460-471"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148509546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved Single PWM Control of Active-Bridge Converters for High Efficiency and Wide ZVS Operation","authors":"Byeng J. Byen;Hae W. Seo;Seul Lee;Eun S. Lee","doi":"10.1109/JESTIE.2025.3642561","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3642561","url":null,"abstract":"A novel control methodology for multiactive-bridge (MAB) converters, termed the single PWM (SPWM) technique, aimed at reducing both conduction and switching losses, is proposed in this article. The proposed control algorithm achieves soft switching across all load conditions while optimizing the converter’s overall conduction loss by minimizing the RMS currents of the three ports for the MAB converters, particularly under light-load conditions. By employing only two control variables—primary and secondary phase shifts (<italic>φ<sub>d</sub></i>) and zero-voltage turn-<sc>on</small> intervals (<italic>α</i> or <italic>β</i>)—the control complexity is significantly reduced compared to conventional MAB control algorithms, which rely on multiple variables and incur high computational overhead. The SPWM control method thus enables efficient and straightforward converter operation under both step-up and step-down conditions. Simulation and experimental results at a 10 kHz operating frequency and 70 kW power delivery demonstrate that the proposed method consistently achieves soft switching and minimizes the RMS currents of all three ports under various voltage and power conditions, leading to efficiency improvements of up to 0.6% compared to conventional SPWM techniques.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"533-544"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantitative Feedback Design Based Robust 2-DOF PID Control of Voltage Mode Controlled DC–DC Buck Converter With Unstructured Uncertainty and Sensor Noise Suppression","authors":"Srikanth Reddy Kalvapalli;R. Jeyasenthil;Tarakanath Kobaku;Yam Siwakoti","doi":"10.1109/JESTIE.2026.3650794","DOIUrl":"https://doi.org/10.1109/JESTIE.2026.3650794","url":null,"abstract":"This article presents a robust control strategy for a Buck-type dc–dc (BTdcdc) converter under voltage-mode control using only output-voltage feedback. Robust control design is challenging due to parametric and unstructured uncertainties, set-point tracking, source-voltage and load disturbances, and high-frequency (HF) sensor noise. To address these issues, a Quantitative Feedback Theory (QFT) based two-degree-of-freedom (2-DOF) control architecture is developed. The advantages of the proposed QFT approach are: 1) 2-DOF control structure comprises PID controller and a prefilter, which provides additional flexibility to improve the output voltage set-point tracking despite model variations. 2) Low transient inductor current leads to subsequent reduced losses. 3) Inclusion of disturbance dynamics and an unstructured uncertainty in the controller loop-shaping design itself. 4) Reduced output voltage deviation for source and load disturbances. 5) Improved suppression of HF sensor noise with less peak-to-peak inductor current and duty ratio variation. Experimental validation on a BTdcdc prototype confirms superior tracking and regulation performance. For source-voltage disturbances, the proposed method reduces peak voltage deviation by 30% –50% and achieves settling times 4–8 times faster. HF noise attenuation is also significantly improved.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"570-580"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148513612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integrated Magnetic Structure to Improve High Power Region Efficiency for Dual Active Bridge Converter","authors":"Siddhesh Shinde;Gautam Rituraj;Gautham Ram Chandra Mouli;Vishnu Mahadeva Iyer;Pavol Bauer","doi":"10.1109/JESTIE.2025.3648204","DOIUrl":"https://doi.org/10.1109/JESTIE.2025.3648204","url":null,"abstract":"In dual active bridge (DAB) converters, series inductor and transformer functionalities are integrated into a single magnetic core structure to improve efficiency or power density. Allowing independent tuning of this integrated series inductance and magnetizing inductance gives higher design flexibility. However, the existing integrated magnetic methods often lower magnetizing inductance, compromise the transformer winding coupling, require complex custom core designs, or cannot effectively decouple transformer and inductor fluxes in the case of separate transformer and inductor windings. To overcome these problems, this article proposes a unified core structure that allows independent tuning of series inductance without the above-mentioned limitations. To demonstrate the performance of the proposed integrated structure, a DAB converter for a dc–dc electric vehicle charging application is built, and the proposed integrated structure is compared with discrete transformer and inductor structures under identical core volume and thermal steady-state conditions. It is experimentally validated that for the proposed structure at a high output voltage and high load conditions of 450 V and 9 kW, the magnetic power loss reduction is 8.8%, whereas, at a low output voltage and high load conditions of 250 V and 7 kW, the magnetic power loss reduction is 13.0%. Furthermore, this article presents an iterative design methodology based on the derived reluctance and analytical models to systematize the design process.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"498-510"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148508134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Generalized Time-Domain Modeling of Dual-Bridge Series Resonant Converters for Control Performance Improvement","authors":"Yaru Deng;Wensheng Song;Shuai Yin","doi":"10.1109/JESTIE.2026.3660259","DOIUrl":"https://doi.org/10.1109/JESTIE.2026.3660259","url":null,"abstract":"Dual-bridge series resonant converters (DBSRCs) are promising solutions to interface energy storage modules with DC-bus flexibly. To compensate for the defect that the fundamental harmonic approximation (FHA) model has high accuracy only near the resonant frequency point, a generalized time-domain model (the G-TDA model) is proposed for DBSRCs, which can accurately describe operating characteristics and transmission power of DBSRCs. In addition, the evolving time-domain models of other symmetric phase-shift modulations are derived from the G-TDA model. Compared with the FHA model, the G-TDA model can predict the resonant current behavior and zero-voltage-switching (ZVS) conditions with higher accuracy. Then, the relationship between backflow power and resonant current is discussed, the backflow power optimization performance is closely related to the prediction accuracy of the resonant current behavior. Besides, dead time effects are analyzed when switching devices achieve/lose ZVS, which is closely related to ZVS conditions. Finally, comparative experiments of optimization methods based on the FHA model and the G-TDA model are carried out, better control performance of the backflow power optimization and the dead time compensation can be achieved due to the higher accuracy of the G-TDA model, such as zero-backflow power optimization, all switching devices ZVS, and efficiency improvement of DBSRCs.","PeriodicalId":100620,"journal":{"name":"IEEE Journal of Emerging and Selected Topics in Industrial Electronics","volume":"7 2","pages":"653-664"},"PeriodicalIF":4.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148513613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}