Cell inconsistency is an inherent challenge for lithium-ion batteries during long-term operation, necessitating the use of battery equalization systems (BESs). In such systems, real-time data communication is essential for ensuring accurate system coordination and effective equalization performance. This paper proposes a distributed BES based on the talkative power converter (TPC) technique, employing a bidirectional flyback converter as the core equalization unit. In the proposed approach, the converter not only transfers energy among distributed battery modules but also modulates data signals for communication. This dual-function design eliminates the need for additional communication hardware or dedicated signal transmission circuits, thereby reducing the overall system complexity. On this basis, a distributed equalization system and its communication channel model are developed. The system noise sources are then analyzed and a noise suppression strategy is proposed to improve the communication reliability. Furthermore, a practical communication protocol tailored to the distributed architecture is designed. Finally, a hardware prototype is constructed and tested, achieving real-time data communication at a rate of 8.33 kb/s. The results verify the feasibility of using switching-ripple-based power and signal dual modulation for communication within distributed BESs.

Switched-capacitor converters (SCCs) are widely adopted in integrated circuits and increasingly used in data centers for their high power density and efficiency.Acomprehensive analysis and selection of SCC topologies for a given conversion ratio is essential for high-efficiency design. Although grid-based synthesis methods enable the generation of numerous novel topologies, evaluating their losses still relies heavily on time-consuming simulations. This is because traditional theoretical analysis methods cannot be applied to “underdetermined topologies”, as their charge multiplier vectors cannot be uniquely determined by conventional methods. In this paper, we propose the dual-limit asymptotic current model and apply it to analyze underdetermined topologies, which constitute 96.61% of 4:1 SCC topologies. By constructing an analysis framework based on this model, we successfully achieved rapid analysis across the full topology space, with an analysis speed 235 times faster than the traditional parallel simulation. Theoretical analysis results were validated through simulations and prototype experiments, identifying several novel topologies that differ from conventional designs while demonstrating favorable efficiency under the evaluated parameter set.

Nine-switch converter (NSC) has been developed as a compact solution for dual-output applications, but its switch-sharing architecture introduces inherent coupling problems between output ports that poses modulation difficulties. This article establishes a decoupled space vector modulation (SVM) model for NSC to address this fundamental challenge. Through analytical reconstruction of the conventional SVM model and decomposition of reference vectors, the proposed modeling method achieves decoupled modulation and independent port control while reducing the complexity of SVM algorithm. Based on the proposed decoupled model, a comprehensive mathematical analysis of the maximum modulation index is derived and the analytical expression formula is obtained, explicitly revealing the phase-dependent linear modulation range of NSC. The performance of the proposed SVM method is validated through simulation and a 400 V, 3 kW experimental prototype and the experiment results exhibit strong agreement with the theoretical analysis of maximum modulation indices.

Peer-to-peer (P2P) energy trading offers a cost-effective solution for energy exchange among microgrids (MGs). However, its widespread adoption faces critical challenges, including network constraints, market fairness and trading sustainability. To address these challenges, this paper proposes a novel distributed P2P energy trading mechanism based on a hybrid game-theoretic framework. The mechanism aims to enhance market fairness through rational pricing of dynamic network usage fees and P2P energy trading prices, thereby fostering the sustainability of P2P transactions. The interaction between the active distribution network (ADN) and the MG alliance is modeled as a Stackelberg game, and the ADN charges the MG dynamic network fees. Internally, a cooperative game based on Nash bargaining is employed to solve P2P energy trading volumes and prices among MGs, ensuring fairness in energy pricing. Moreover, the fairness of the proposed pricing mechanism is analyzed using the Gini coefficient. Finally, simulation results on the IEEE-33 bus system demonstrate that the fair and dynamic pricing mechanism can achieve near-optimal social welfare, promoting P2P energy trading among MG and ensuring a win-win scenario for ADN and MGs.

In the fuel assembly design of pressurized water reactors, helical cruciform fuel (HCF) rods have garnered significant attention due to their substantial potential for enhancing thermal-hydraulic performance and achieving higher safety margins. However, the complex geometry of HCFassemblies leads to prohibitively high computational costs for full-scale CFD simulations, severely restricting their application in design optimization. This paper develops a reduced-order model named HyPOD-AdTransformer to achieve efficient prediction of flow and heat transfer characteristics in HCF assemblies. The model incorporates a hybrid reduced-order algorithm (HyPOD), which employs traditional proper orthogonal decomposition (POD) for velocity field processing and proposes explicit boundary POD (EbPOD) for the temperature field to retain critical boundary layer information, thereby improving the applicability of traditional POD for temperature field analysis. Additionally, the AdTransformer is integrated to enhance the model's capability in capturing nonlinear features and global fullfield information, improving its ability to represent the complex flow characteristics induced by the HCF helical structure. This reduces prediction errors in the temperature field boundary layer and the mainstream region of the velocity field. Case analysis demonstrates that compared to POD-BPNN (with average errors of 0.29%, 10%, and 1.1% for u, w, and T respectively), the prediction errors of HyPOD-AdTransformer are reduced to 0.00095%, 0.25%, and 0.013%. This model takes boundary conditions as input and directly outputs the full-field distribution without requiring CFD iterations, providing a reliable method for efficient thermal-hydraulic analysis and flow field prediction in complex structures.

The single-stage, isolated three-phase dc-ac converter presents significant advantages for applications involving low dc voltages. By eliminating the need for large capacitors, this design facilitates a more compact physical layout. However, the complexity inherent in modulation strategies frequently gives rise to substantial three-phase current harmonics, which adversely affect system performance. Despite numerous efforts documented in the literature to enhance various performance metrics, the effectiveness of these solutions has often been found to be limited. This article presents a new modulation strategy designed to enhance the overall performance of high-frequency link matrix converters. We utilize frequency domain analysis through Fourier transform for our modeling approach. Our strategy optimizes performance by employing a combination of dual shift phase angles and dual modulation indices. Finally, the validation of this strategy was conducted on a three-phase 800 W prototype. Experimental outcomes demonstrated a Total Harmonic Distortion below 2% using a single DSP controller, corroborating theoretical model which predicted a reduction in current stress to 84% of its initial level, and the peak value of low-frequency fluctuation is reduced to 72-78%.

In battery management systems, the ac bus-based modular equalizer, typically connected to a common ac link, enables fast and flexible power balancing. However, the reliance on synchronized control signals and dedicated communication links increases the wiring complexity. This article proposes a modular equalizer embedded with power line communication (PLC), leveraging the ac bus for simultaneous power and data transmission. Based on this, a distributed control scheme is proposed, where modular equalizers communicate via PLC to share state of charge and receive target power commands, while adjusting their power outputs based solely on local measurements. This scheme eliminates the need for synchronous drive lines and dedicated communication links, thus simplifying wiring and enhancing scalability. The stability of the distributed control strategy is proven, guaranteeing reliable power flow. Crosstalk analysis confirms tolerable mutual interference between power balancing and data transmission without functional degradation. Finally, experimental results from a four-equalizer prototype demonstrate the effectiveness of the proposed PLC-embedded modular equalizers.

In magnetically coupled resonant (MCR) wireless power transfer systems, intermediate coils are used to extend power transfer distance. The complex magnetic coupling among multiple coils poses a challenge for simultaneous wireless power and data transfer. Wireless power and information dual transfer (WPIDT) is recently proposed to modulate the transmitting data on one dc side and receives it on the other dc side. In this article, the design and optimization of WPIDT systems with any number of intermediate coils is investigated. First, a general reduced-order model of the multicoil MCR channel is developed. The information transmission properties are analyzed in the model by scattering parameters. Accordingly, the matching circuits for communication are studied to optimize for higher transfer gain. The transfer gain can be simultaneously optimized for both upward and downward communication in a symmetrical coil arrangement. Finally, a 27.7-W five-coil WPIDT prototype system is developed and tested to validate the theoretical analysis. The experiments achieve bidirectional data transfer at 20kbps.

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 (dv/dt) 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.

To adapt to the application scenarios of low-voltage dc sources, the traditional voltage source inverter requires additional preboost circuits for their utilization in low voltage applications. This led to inception of differential inverters which constitute a topology capable of integrating both boost and inversion functions within a single stage, making them a promising alternative to two-stage inverters. However, the existing static gain modulation scheme (SGMS) for differential inverters overlooks the nonlinear phenomena induced by the dynamic variation of converter gain, causing inevitable harmonic distortion in the output voltage. This article discusses the nonlinear harmonic distortion and proposes a dynamic gain modulation scheme (DGMS) for differential inverters. This scheme models both boost-type and buck-boost-type differential inverters using a unified mathematical model. A more accurate modulation function is adopted by employing approximate solutions to the state equations, effectively reducing harmonic components in load voltage compared to SGMS. The experiment results validate that DGMS significantly lowers total harmonic distortion and effectively enhances the quality of the output voltage waveform, demonstrating its considerable potential for practical applications.

Film Capacitors are widely used in modular multilevel converter (MMC) systems due to their high reliability and long-life characteristics. However, the degradation of film capacitors vulnerable to humidity and temperature can reduce the MMC system’s dependability. Since it can be tricky to anticipate variations in humidity and temperature and the aging model-based external stress mission profile may lead to significant deviation, this paper proposes a remaining life estimation methodology by fusing real-time updated degradation data. In the proposed methodology, a quadratic polynomial is used to fit the aging curve of capacitor based on the degradation data. Because the proposed method is a dynamic scheduling algorithm, it is free of external stress. The effectiveness of the proposed method is verified, and the results show that it has a good performance.

The single-phase differential boost inverter (SPDBI) possesses unique single-stage boost capability, which conventional voltage source inverters lack. While the discontinuous modulation strategy offers superior efficiency advantages, the inherent nonlinear distortion issues in SPDBI remain unresolved. This paper proposes a dual-loop control strategy based on pulse train control, which achieves excellent voltage tracking and dynamic performance through well-designed duty cycles for two pulse train sets. Simulation and experimental results validate the effectiveness of the proposed control strategy.

To address the current distortion problem of grid-forming inverters in weak grids, a harmonic current suppression method based on hybrid feedforward is proposed. Firstly, from the perspective of the output impedance of grid-forming inverters, an impedance model is established and an improved Proportional-Resonant (PR) controller is proposed to suppress harmonic current at the rated frequency. However, the bandwidth of the PR controller is relatively narrow, and its effect will be greatly weakened when the grid frequency deviates. To address this issue, a high-pass filter is used to feedforward the grid-side current to suppress harmonics within a wide frequency range. Additionally, to enhance the stability of inverters in weak grid conditions, phase compensation is carried out in the high-frequency band. Compared with the existing harmonic suppression methods, this method can achieve better harmonic current suppression effect within the range of grid frequency fluctuations. The simulation results have proved the effectiveness of this method.

Recently, the Three-Load Twelve-Switch Inverter (TLTSI) has emerged as a promising solution for multi-motor drive systems due to its advantages in switch count reduction and system integration. However, existing studies have been confined to a basic carrier-based pulse-width modulation (PWM) under synchronized operating conditions, limiting its practical applications. To overcome this constraint, this paper presents a comprehensive space vector modulation (SVM) method specifically developed for TLTSI. The proposed method enables flexible control under both synchronous and asynchronous operation modes, accommodating outputs with different frequencies and phase shifts. The proposed modulation strategy is verified through experimental results, demonstrating excellent modulation performance.

In wireless power transfer (WPT) systems, effective communication between the transmitter and receiver is crucial for precise control and system monitoring. To address this need, simultaneous power and information transfer (SWPIT) has been extensively studied. However, SWPIT implementations often require additional coils or circuits, which complicates the overall system. This work presents the design and numerical experiments of a minimal SWPIT system. The auxiliary modulation circuits are simplified using phase shift control in the inverter, while multi-carrier modulation can be embedded to enhance frequency band utilization. Similarly, auxiliary demodulation circuits are simplified by leveraging the frequency-mixing effect in the rectifier. The proposed minimal SWPIT method is adaptable across diverse compensation networks. The key transfer characteristics of the compensation network are cloned in the information transmission, enabling load-independent communication. Simulation results confirm the theoretical analysis, demonstrating the transfer characteristics and elasticity of the minimal SWPIT system.

This article critically reviews ongoing and recently completed international research and development projects in the field of smart inverter technologies for photovoltaic (PV) systems, emphasising publicly funded projects worldwide. By identifying common objectives, outcomes, innovations, and shortcomings across the projects, the review highlights critical gaps-such as the lack of cybersecure inverter firmware, under-addressed electromagnetic compatibility (EMC), and limitations in power density and predictive maintenance frameworks. Recommendations for future research include a co-designed approach integrating wide-bandgap semiconductors, digital twin-enabled predictive control, and standardisation contributions. The paper will act as a strategic roadmap for researchers, policymakers, and industry stakeholders, guiding the next generation of smart inverter development by consolidating global insights, pinpointing unresolved challenges, and proposing multidisciplinary solutions that bridge the gap between academic innovation and real-world deployment.

With the development of power system and the large-scale application of power electronic devices in power grid the harmonic problems have gradually become the focus of attention. Harmonic detection algorithm is very important in harmonic elimination device. The traditional harmonic detection method in multi-synchronous rotating coordinate system utilizes a low-pass filter(LPF), and the accuracy of detection results depend on the performance of the filter. Meanwhile, the detection of negative-sequence and zero-sequence components resulting from load asymmetry in power grid should also be taken into consideration. Therefore, this paper proposes a multi harmonic detection method based on the periodic mean method in the multi-synchronous rotating coordinate system. The corresponding treatment methods of positive sequence and negative sequence harmonics for unbalanced power grid are summarized. The simulation results show that the proposed periodic mean multi-synchronous rotating harmonic detection method can effectively extract the different harmonic components in the power grid and can achieve no static error detection.

Three-phase, four-wire, three-level inverters may experience high zero-sequence current in neutral wire, due to mechanical delays in switching devices, and load or system imbalances in microgrids. The neutral current not only causes line losses but also affect the stability of the power system. Therefore, this paper proposes a 3D-SVM modulation method applied to three-phase, four-wire, three-level inverters. The full vector space of the three-phase, four-wire, three-level inverters is reasonably divided in three dimensions according to the nearest vector principle. Compared to traditional SVM, the proposed method controls the zero-sequence current from a modulation perspective, possessing the ability to regulate the zero-sequence component. Simulation and experimental results demonstrate the effectiveness of the proposed modulation method in controlling zero-sequence current.

Microgrids have become increasingly important because of the global shift toward energy decarbonisation and decentralisation. These modular networks enable communities to integrate local renewable energy sources, enhance energy security, and empower consumers to control their energy supply. Meanwhile, the spread of smart meters and IoT sensors provides high-resolution electricity usage data, driving the design of microgrids that utilise machine learning for demand-side insights. Current microgrid studies primarily focus on supply concerns, including generation, control algorithms, and economic optimisation, often overlooking the optimal selection and configuration of households based on detailed consumption behaviour. This gap is important; ignoring diverse household load profiles skews community demand and misses optimal energy-sharing opportunities. Greater load diversity reduces coincident peak demand and enhances resource usage. Conversely, homogeneous loads lead to poor energy sharing, oversized infrastructure, and less efficient demand response. We introduce an XAI-informed residential household clustering method for community microgrids (XAI-RHCCM). K-means clustering organises households by average daily energy use, identifying natural consumption types. An artificial neural network, optimised with Bayesian techniques, classifies new households into these clusters, with Shapley Additive Explanations highlighting the consumption features influencing the classification. XAI-RHCCM combines unsupervised clustering, predictive modelling, and interpretability, focusing on demand heterogeneity in microgrid configurations.

With fossil fuels as a major global energy source and their associated carbon emissions impacting the climate, there is an urgency in transitioning to carbon-free energy sources (CFESs) such as nuclear and renewables (solar, hydroelectric, and wind). The need for an updated electric power transmission and distribution system arises due to the variable loads and geographic diversity of renewable energy sources. This perspective explores the idea of the "Earth Grid," which proposes an intercontinental electric grid facilitated by three technological advancements: enhanced information and communication technology (ICT) applications in the electric grid, development of inter-country grids for power-sharing, and the application of artificial intelligence (AI) for efficient operation and maintenance. Further, the article discusses the need for a collaborative effort on the global stage to transform the existing electricity generation, transmission, and distribution sector to create a globally interconnected carbon-neutral Earth Grid infrastructure for accelerated carbon-free energy access for all.