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The integration of large-scale photovoltaic (PV) systems requires advanced converter architectures capable of ensuring both high efficiency and fast dynamic response. Leveraging the inherent modularity and low harmonic distortion of Modular Multilevel Converters (MMCs), this paper presents a novel control and modulation framework for grid-connected PV applications. The key innovation lies in the implementation of distributed, string-level Maximum Power Point Tracking (MPPT), enabling optimal energy extraction even under non-uniform (shaded) irradiance conditions. The proposed method operates within a dual time-scale control architecture: an outer Perturb and Observe (P&O) loop assigns independent power references, while the inner modulation stage employs an innovative switching strategy that activates only one module per sampling period. Unlike conventional MPPT-based schemes, where submodules are driven by voltage references, the proposed approach directly regulates the power of each MMC submodule, eliminating the need for PV-side current measurement.

Introduction. Wind energy conversion system is getting a lot of attention since, they are provide several advantages, such as cost competitive, environmentally clean, and safe renewable power source as compared with the fossil fuel and nuclear power generation. A special type of induction generator, called a doubly fed induction generator is used extensively for high-power wind energy conversion system. They are used more and more in wind turbine applications due to the advantages of variable speed operation range and its four quadrants active and reactive power capabilities, high energy efficiency, and the improved power quality. Wind energy conversion systems require a good choice of power electronic converters for the improvement of the quality of the electrical energy produced at the generator terminals. There are several power electronics converters that are the most popular such as the two stage back-back converter. Because of the disadvantage of these converters to produce large harmonics distortions, we will choose using of three-phase matrix converter. Purpose. Work presents a direct power control using space vector modulation for a doubly fed induction generator based wind turbine. The main strategy control is to control the active and reactive powers and reduce the harmonic distortion of stator currents for variable wind speed. The novelty of the work is to use a doubly fed induction machine and a three pulses matrix converter to reduce the low cost, volume and the elimination of the grid side converter controller are very attractive aspects of the proposed topology compared to the conventional methods such as back-to-back converters. Simulation results are carried out on a 1.5 MW of wind energy conversion system connected to the grid. The efficiency of the proposed system has been simulated and high results performances are evaluated to show the validity of the proposed control strategy to decouple and control the active and reactive power for different values of wind speed.

Power electronics and communication electronics are both based on electromagnetic theory, but they are usually regarded as two distinct subfields in electrical engineering. In fact, however, electric power is the most common matter-based carrier of messages; thus, power electronics and communications can be jointly considered. Here we study the essential nature of dc-dc power converters and characterize the similarity of their operation principle to that of communication systems. Based on this similarity and the double modulation methods used in power electronics and communication, a double modulation strategy for both power and data is presented and applied in dc-dc power converters to achieve what we call ‘talkative power’. A modulation strategy called frequency hopping-differential phase shift keying (FH-DPSK) is also presented to overcome the crosstalk between chosen transmission systems. The proposed talkative power strategy sheds new light on and provides inspiration for the further development of power electronics and communication. Designing efficient power and communication electronics remains a challenge. Here, the authors reveal info characteristics of power electronics and propose a modulation strategy based on frequency hopping-differential phase shift keying to enable power converter design integrated with communication.

Renewable Energy Sources (RES) showed enormous growth in the last few years. In comparison with the other RES, solar power has become the most feasible source because of its unique properties such as clean, noiseless, eco-friendly nature, etc. During the extraction of electric power, the DC–DC converters were given the prominent interest because of their extensive use in various applications. Photovoltaic (PV) systems generally suffer from less energy conversion efficiency along with improper stability and intermittent properties. Hence, there is a necessity of the Maximum power point tracking (MPPT) algorithm to ensure the maximum power available that can be harnessed from the solar PV. In this paper, the most important features of the DC/DC converters along with the MPPT techniques are reviewed and analyzed. A detailed comprehensive analysis is made on different converter topologies of both non-isolated and isolated DC/DC converters. Then, the modulation strategies, comparative performance evaluation are addressed systematically. At the end, recent advances and future trends are described briefly and considered for the next-generation converter’s design and applications. This review work will provide a useful structure and reference point on the DC/DC converters for researchers and designers working in the field of solar PV applications.

Increased performance requirements in new power electronics areas of application, such as electric aircraft, make innovations on different design levels necessary. In order to quickly compare different topologies, analytical loss equations provide a fast and straightforward way to narrow down the possible solution space. The approach widely used in the literature results in long and complex terms, which can only be compared between different literature sources with great effort. Moreover, the literature lacks a detailed summarizing description of these analytical equations and their derivation, starting from the standard two-level VSI up to three-level midpoint clamped inverter topologies, such as the ANPC topology in its different modulation schemes. The application of such higher-level inverter topologies allows hybrid device configurations to become performant solutions. This work aims to give a closed-form description of the analytical loss modeling and the theoretical background and provide an implementation approach for a wide span of inverter topologies and for different modulation methods.

A hybrid control strategy is proposed for a SS compensated three-phase wireless power transfer (3P-WPT) system, which realizes full zero-voltage switching (ZVS) operation of the converter during the entire charging process of a battery. First, a mathematical equivalent model of 3P-WPT is established by fundamental harmonic approximation, the ZVS operation of the active bridge in the constant current (CC) charging mode is optimized by considering the relationship between the input impedance, operation frequency, and duty cycle. Consequently, an optimal modulation strategy featuring full ZVS operation is proposed for the constant current and constant voltage (CV) charging modes of 3P-WPT. Second, based on the NSGA-II algorithm, a mathematical model for the multi-objective optimization of coils is established, which aims for a high transmission frequency and power density. The parameters of coils are optimized accordingly. Finally, a 2 kW experimental prototype is built. Experimental results verify the effectiveness of the proposed control strategy, where the maximum efficiency is up to 90.26% at a full load.

Distinct from the traditional Modular Multilevel Converter (MMC) which focuses on fundamental frequency operation, the Static Var and Filter (SVF) within the Multi-Source Line-Commutated Converter (SLCC) system is tasked with the core function of high-frequency harmonic filtering. This paper reveals a unique engineering reliability issue stemming from this functional difference: to satisfy the Nyquist sampling theorem for precise tracking and elimination of high-frequency harmonics, the update frequency of the capacitor voltage balancing algorithm in the SLCC-SVF system is forced to increase significantly. Mathematical modeling and quantitative analysis demonstrate that this strong coupling between harmonic tracking demands and the voltage sorting strategy directly drives an abnormal surge in the average switching frequency (reaching over five times that of the fundamental condition), severely threatening device safety. To address this, an optimized adaptive hybrid modulation strategy is proposed. The system operates under Nearest Level Modulation (NLM) in normal conditions and automatically transitions to Carrier Phase-Shifted PWM (CPS-PWM)—leveraging its closed-loop balancing capability—when switching frequency or junction temperature exceeds safety thresholds. Furthermore, a non-integer frequency ratio optimization theory for low-modulation indices is constructed specifically for SVF conditions to prevent low-frequency oscillations. PLECS simulation results validate the theoretical analysis, showing that the proposed strategy effectively reduces the average switching frequency by approximately 20% under complex harmonic conditions, significantly enhancing thermal stability and operational reliability while guaranteeing filtering performance.

Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems.

Due to the problems of serious circulation current, large switching loss, high harmonic content, unstable voltage, and high engineering cost in existing microgrid structures, a micro-source half-bridge converter series Y-connection-based microgrid (HCSY-MG) is proposed in this paper. On the basis of the equivalent circuit in the system islanding state, the output characteristics of the system and the corresponding influencing factors under both square wave modulation and phase-shifted pulse width modulation (PS-PWM) are analyzed. Under single-cycle square wave modulation, since the DC-side capacitors of some micro-source half-bridge converters are affected by reactive power, which can result in system output voltage fluctuations or even an in-phase imbalanced state, a multi-period cycle modulation strategy is applied to solve this problem. Under the PS-PWM strategy, if the modulation degree and capacitance of the micro-source half-bridge converters are reasonably set, the output voltage of the system can be guaranteed to be in an in-phase equilibrium state. A simulation model and an experimental platform are built to verify the feasibility of the system and the effectiveness of the proposed strategy.

In this paper, a new generalized step-up multilevel DC-AC converter is proposed, which is suitable for applications with low-voltage input sources, such as photovoltaic power generation and electric vehicles. This inverter can achieve a high voltage gain by controlling the series-parallel conversion of the DC power supply and capacitors. Only one DC voltage source and a few power devices are employed. The maximum output voltage and the number of output levels can be further increased through the switched-capacitor unit's extension and the submodule cascaded extension. Moreover, the capacitor voltages are self-balanced without complicated voltage control circuits. The complementary operating mechanism between each pair of switches simplifies the modulation algorithm. The inductive-load ability is fully taken into account in the proposed inverter. Additionally, a remarkable characteristic of the inverter is that the charging and discharging states among different capacitors are synchronous, which reduces the voltage ripple of the front-end capacitors. The circuit structure, the working principle, the modulation strategy, the capacitors and losses analysis are presented in detail. Afterwards, the advantages of the proposed inverter are analyzed by comparing with other recently proposed inverters. Finally, the steady-state and dynamic performance of the proposed inverter is verified and validated by simulation and experiment.