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The direct transformation of alkylboron has emerged as a versatile and powerful methodology for creating carbon–carbon and carbon–heteroatom bonds. However, its potential application in the formation of carbon and phosphorus remains unexplored. In this study, we present an alkoxide base-promoted reaction system that enables deborylative phosphination of benzylic organoboronates and geminal bis(boronates) via selective C–B bond cleavage. This approach allows for the synthesis of valuable tertiary phosphines in good yields under mild conditions. The practicality and industrial potential of this approach are underscored by the operational simplicity, broad substrate scope, and easy scalability.

In islanded ac microgrids with heterogeneous distributed generations (DGs), secondary frequency control (SFC) can restore the frequency that deviates from the nominal level due to the primary P-f droop control. Traditionally, to realize SFC, the instantaneous frequency needs to be directly measured or estimated to produce frequency compensations, which increases system cost and complexity. In this article, a new spatial load power forecasting for distributed secondary frequency control (SLPF-DSFC) based on artificial neural networks is proposed. Without frequency measurement, it can effectively eliminate frequency deviations and autonomously cope with various load changes by optimizing active power outputs from DGs. The distributed average and pinning protocols based on graph theory are also included. Comprehensive case studies demonstrate that the proposed SLPF-DSFC method shows superior performance over conventional SFC approaches in terms of frequency stabilization and voltage harmonics reduction during load variations, SFC startup/shutdown, as well as communication delays.

This article proposes a new method for simultaneous dynamic wireless power and data transfer (SDWPDT). When the receiver is moving, both power and data transfer channels are dynamically switched ON/OFF according to the receiver’s position. In essence, data are transmitted through the high-frequency electric field (EF) generated by the parasitic capacitances of the coupling coils and the metal shield plates, while power is transmitted through the relatively low-frequency magnetic field (MF) generated by coupling coils. By doing this, mutual interference between two transfer channels (i.e., power and data transfer channels) is relatively small. First, the interference from power to data can be greatly reduced due to the absence of a direct electrical wire-based connection. Second, the power loss caused by the data transfer channel in the power link is very small, so it can be ignored. In addition, the implementation of real-time communication facilitates the establishment of closed-loop control within the system. This mechanism guarantees consistent power output during dynamic movement, even in the presence of fluctuations in load or input voltage. Laboratory prototype-based experimental findings substantiate the feasibility of the proposed approach.

This brief introduces a design of the magnetic coupler tailored for unmanned aerial vehicles (UAVs), distinguished by its robust capability to counteract misalignments, ensuring consistent and reliable charging. This resilience extends beyond mere angular misalignment, also encompassing ${x}$ - and ${y}$ - deviations, a testament to the efficacy of the presented magnetic coupling design. The transmitter $(T_{\mathrm{ X}})$ incorporates eight solenoid coils, establishing a magnetic field that spans from the core to the periphery. To capitalize on this magnetic field, two rectangular coils have been strategically mounted on the landing gears, aligning with the inherent geometry and space constraints of standard commercial UAV landing apparatus. The employment of air-core receivers also serves to mitigate on-board weight. This meticulously crafted coupling mechanism empowers the system with an impressive capacity to accommodate a full 360° of angular misalignments, in addition to a considerable horizontal offset range of (–50 mm,–50 mm) $\leq {O}\,\,{=}$ (x, y) $\leq $ (50 mm, 50 mm). Both finite element analysis (FEA) and an experimental prototype have been employed in this brief. The outcomes align congruently with theoretical projections, showcasing output voltage variations of ± 0.3%, ± 1.8%, and ± 1.4% for angular, ${x}$ -axis, and ${y}$ -axis misalignments, respectively.

Maximum efficiency point tracking (MEPT) is a key concept to improve the ac-ac efficiency of the wireless power transfer (WPT) systems by controlling the equivalent load impedance with a dc-dc converter or an active rectifier. The on-off keying (OOK) modulation can reduce the switching losses of the converters to achieve MEPT but generates relatively large dc voltage ripples. In order to solve this problem, this article proposes an enhanced on-off keying (EOOK) modulation method by adding a half-bridge mode based on OOK modulation for WPT systems. By combining the three operation modes, both the inverter and the active rectifier can operate in full-bridge-half-bridge mode or half-bridge-zero mode to adapt to different power levels and achieve MEPT simultaneously. Meanwhile, the ZVS condition and the low voltage ripple are achieved as well. The circuit model of the proposed method is analyzed to derive the equivalent load resistance, the output voltage gain, and the output power with respect to the modulation of EOOK. The reason for output voltage ripples and the power losses on both the transmitting and receiving sides are also revealed. An experimental prototype is built to verify the effectiveness of the proposed method. The experimental results show that the proposed method can maintain constant voltage output and achieve MEPT as well as ZVS operation, with high efficiency of up to 94.761% over a wide range of load conditions.

This article proposes a 1-ϕ transformer-less inverter for grid-tied PV systems. The proposed inverter has the capability to produce five distinct voltage levels at the output stage. Moreover, it is a compact switched-capacitor (SC) based design that incorporates eight power switches, an ultra-fast power diode, and two electrolytic SCs. This topology reduces the number of power electronic components, resulting in decreased cost and weight. Due to the direct connection of the negative dc line of the proposed inverter to the null of the grid voltage, the leakage current is completely removed for PV application. Another advantage of this topology is that it can easily boost the output voltage by a factor of two without the need for any magnetic or active devices. During the grid voltage period, the SC's are charged in series with the input voltage, resulting in automatic balancing. As a result, the proposed inverter eliminates the need for a complex control method to balance the SC's. Design guidelines have been developed for the proposed inverter. Also, the quantitative comparative study with similar five-level topologies is presented to show superiority of the proposed inverter. Moreover, the proposed inverter alongside a PV system is simulated to demonstrate the capability of the proposed inverter in a closed-loop D-Q control system. This topology is validated using a laboratory prototype for a 1 kW system at a grid-tied connection.

Microgrids have emerged as a promising solution to integrate distributed energy resources (DERs) and supply reliable and efficient electricity. The operation of a microgrid involves the coordination of different DERs and loads. To date, various control methods have been developed to maximize the overall benefit while satisfying various constraints. Now it is urgently needed to understand and comprehend these approaches to further stimulate the deployment of microgrids. This paper presents an overview for researchers on economic model predictive control (EMPC) methods of microgrids to achieve a variety of objectives such as cost minimization and benefit maximization. The fundamental principle of the EMPC theory is explained in detail. The most popular and important strategies applied to stand-alone microgrids, grid-connected microgrids, residential smart homes, as well as networked microgrids are discussed. Future trends are also highlighted.

Wide output voltage range applications are challenging for wireless power transfer systems. Under conventional single-mode control [i.e., single full-bridge (FB) or single half-bridge (HB)] based on phase-shift modulation, the system efficiency would be degraded when satisfying wide voltage gain requirement, especially in low gain. The main reason is that wide output voltage regulation requires the conducting angle varying in large operating ranges. When pulsewidths of the square voltage are adjusted to narrow, the switching loss increases and the system efficiency decreases significantly. Therefore, to address the abovementioned issue, in this work, a multimode control is proposed for wide output voltage range applications. Using the multimode control, the inverter can operate in HB mode, HB–HB mode, and FB–HB mode. Compared with an FB inverter, the conducting angle can be effectively maintained larger, and all the switches can realize zero-voltage-switching in a wide range. Thus, the system efficiency can be improved significantly. Furthermore, the online mutual inductance detection unit is not necessary. A 1.7 kW experimental prototype is built to verify the feasibility and effectiveness of the proposed method. The results show that the proposed system can achieve high efficiency from 91.5% to 97.1% under a wide output voltage range.

Three-level T-type converters $ {(3L} {T}^{ {2}} {C)}$ with LCL filters are widely used in distributed generation (DG) systems because of their smaller size and better harmonic attenuation. The $ {3L} {T}^{ {2}} {C}$ have many control objectives such as neutral-point (NP) voltage balancing, resonance damping, and grid current tracking. Therefore, model predictive control (MPC) with excellent dynamic characteristics and multiobjective control capability has become the most common control method. However, MPC control relies on accurate mathematical models, and the existing integer order modeling ignores its fractional-order characteristics. The reflected physical characteristics are not sufficient, so an accurate model is needed to improve the control performance. In this article, we propose a fractional-order state-space model based on the Grünwald–Letnikov (GL) definition and investigate a fractional-order sequential model predictive control (FOSMPC). First, the GL definition is used to establish the state-space model of the fractional-order grid-connected converter to realize the discretization processing and numerical calculation of the fractional-order system. Second, the multiobjective lexicographical optimization method is used to realize the SMPC to balance the NP voltage and grid-connected current reference tracking. Finally, the effectiveness of FOSMPC in controlling fractional-order $ {3L} {T}^{ {2}} {C}$ was experimentally demonstrated.