This article proposes a new bidirectional isolated LLC resonant converter, which is suitable for ultra-wide voltage gain range applications, such as electric vehicle charging systems. The inverter and rectifier of proposed topology both have two modes by reconfiguring different modulation schemes during bidirectional operation. This results in three voltage-gain ranges, allowing ultrawide output voltage operation over narrow modulation frequency. The conversion ratio and resonant tank can be designed for only a quarter of the required output voltage range. Finally, the proposed topology and analysis are validated by experiments results obtained from the converter prototype built in the laboratory.

The paper provides an overview of how Artificial Intelligence (AI) is applied in designing highfrequency magnetic components, primarily high-frequency inductors and transformers, for power electronics systems. Four categories of AI, including expert systems, fuzzy logic, metaheuristic methods, and machine learning techniques, are addressed. Firstly, AI models for estimating losses in high-frequency magnetic components are discussed. Subsequently, AI-based design methods in high-frequency inductors and transformers are observed. Then, AI tools applied to the automatic design of high-frequency magnetic components are introduced and compared. Drawing insights from an analysis of over 200 publications, the paper highlights significant advancements: the development of AI-driven models for precise loss estimation in highfrequency magnetic components, the application of AI in optimizing design configurations for the components, and the automation of design processes. These achievements demonstrate AI's capability to enhance the efficiency, performance, and innovation in high-frequency magnetic component design, offering a roadmap for future research in power electronics systems.

This article tackles the complex challenge of predicting magnetic iron losses in high-frequency magnetic components by introducing a novel conditional generative adversarial network model. Diverging from traditional loss prediction methodologies that often overlook intricate interactions of factors, our conditional generative adversarial network framework is designed to comprehensively incorporate diverse aspects such as material properties, geometrical variations, and environmental conditions. To facilitate this advanced approach, a specialized four-wire measurement kit was employed, which significantly enriched the training dataset with a wide range of measurements. When benchmarked against conventional deep neural network models, the conditional generative adversarial network not only achieves faster convergence but also demonstrates markedly superior accuracy in predicting iron losses. This superiority is particularly notable in scenarios that extend beyond the training data's range, underscoring the model's robustness and adaptability. Such advancements in predictive accuracy and efficiency represent a significant leap forward in the design and optimization of high-frequency magnetic components.

Zero-phase-angle (ZPA) operation is considered as a method to minimize the volt-ampere (VA) ratings and maximize transfer power to the load in the inductive power transfer (IPT) system. However, the ZPA operating prerequisite is quite sensitive to the variation of parameters such as IPT system coupling coefficient and load conditions. A parallel-series/series (PS/S) current-fed IPT system with a new variable capacitors (VCs) structure is proposed to achieve ZPA operation and constant output voltage at fixed frequency. The detailed analysis and mathematical model of the variable capacitors network are reported. The proposed VCs structures in PS/S current-fed IPT system are discussed, analyzed and compared with existing competitive topologies in the literature. The experimental results obtained from 65-W lab-prototypes are demonstrated to verify the analysis and performance.

This paper proposes a novel bidirectional isolated LLC resonant converter to realize wide output voltage range. The proposed converter overcome the dilemma of conventional LLC resonant converter between wide voltage gain and wide switching frequency range. It is achieved by the two operation configurations when the switches of configurable structure (CS) adopt different duty cycle. The CS is beneficial to narrow switching frequency range and increase magnetizing inductance of the converter that benefits the design of the magnetic components and reduces the conduction losses, respectively. Meanwhile, the switching frequency doubler modulation (SFDM) that makes the frequency of the resonant tank twice the switching frequency is adopted to further reduce the size of resonant components and greatly reduce switching losses. Moreover, the proposed converter can achieve soft-switching which ensures high efficiency throughout the wide voltage gain for both forward and reverse operation. In addition, the voltage stress of all switches is halved compared to full- bridge and half-bridge converters. The simulations and a 100W prototype have been built to verify the operation principal and its performance.

The interleaved Boost resonant converter is a well-known topology for applications requiring high step-up ratios, such as photovoltaic (PV) applications. It features its step-up capability, low input current ripple, and soft-switching characteristics. Nevertheless, designing Boost inductors presents challenges. If the Boost inductance is too large, it results in a significant DC component in the inductor current, making it challenging to achieve soft switching on the low-voltage side. Conversely, if the Boost inductance is too small, it leads to a large peak-to-peak boost inductor current, increasing magnetic core losses. There is also a trade-off between boost inductors and magnetizing inductance, impacting conduction loss. This paper addresses these challenges by introducing an auxiliary inductor that facilitates full-range soft-switching. Although the auxiliary inductor will bring losses, it is possible to reduce the overall system loss based on the overall system loss. Additionally, the implementation of a quadruple rectifier reduces diode voltage stress, decreasing costs and diode losses. It also contributes to a low turn ratio transformer and reduced transformer size as well as losses. Finally, a 330W prototype operating with input voltage ranging from 44V to 66V and an output between 250V and 440V is presented to validate the proposed concept.