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The operational performance of grid‐connected active front‐end converters (AFEs) faces challenges arising from the intricate interplay among phase‐locked loop (PLL) non‐linearities, grid impedance, and conventional control strategies, resulting in compromised stability. This study introduces a refined approach to dynamic model predictive control (MPC) by integrating recursive least squares (RLS) for the precise estimation of physical model parameters, thereby addressing stability concerns. Unlike conventional methodologies, the proposed enhanced RLS‐based MPC approach, equipped with an auto‐tuning feature, allows for the design of controllers without a prerequisite understanding of exact external dynamics. Notably, this technique exhibits exceptional disturbance rejection capabilities. The evaluation of the cost function at each sampling interval facilitates the determination of optimal switching states based on predicted variables. Gate pulses for the switches of the AFEs are generated accordingly. Employing a simulation platform, the proposed control structure's performance across varied conditions is comprehensively assessed, encompassing alterations in grid impedance and system non‐linearities. The method adeptly integrates inherent non‐linearities within the system, showcasing exceptional robustness in diverse dynamic scenarios. To further substantiate the efficacy of the proposed control system over conventional approaches, simulation results are validated using a laboratory hardware platform equipped with Typhoon HIL and dSPACE real‐time emulators, providing tangible evidence of the proposed control system's effectiveness in real‐world hardware setups. The multifaceted approach, encompassing precise parameter estimation, predictive control, auto‐tuning, disturbance rejection, robust design, and real‐time evaluation, collectively establishes a resilient foundation for enhancing and maintaining the overall stability of the system across diverse operating scenarios. [ABSTRACT FROM AUTHOR]

This research introduces a novel design of a metamaterial absorber having the range in terahertz, capable of sensing changes in the refractive index of the encircling medium. The layout includes adjoining rectangular patches in the form of a plus symbol along with four circular patch resonators (CPRs) on the pinnacle of a Gallium Arsenide (GaAs) substrate. The proposed design comes up with three consecutive absorption peaks, with an absorptivity of 99.0%, 99.75%, and 98.0% at three different resonant frequencies of 2.36 THz, 2.675 THz, and 2.97 THz, respectively, and a Full Width Half Maximum (FWHM) of 0.08, 0.04, and 0.05. This structure's quality factor (Q-factor) at the three resonant frequencies is 29.5, 66.8, and 59.4 together with 6.75, 17.5, and 30 as figure of merit (FoM), respectively. The proposed design offers a sensitivity of 0.54 THz/RIU, 0.7 THz/RIU, and 1.5 THz/RIU in those three absorption bands. To support the selection of design parameters, parametric assessment was done. The designed sensor can find its applications in terahertz sensing. [ABSTRACT FROM AUTHOR]

Summary: A vast community of developing countries, like India, is still deprived of a proper water supply system. Such communities often depend on hand‐pumps, ponds, and ravines for their daily water needs. Government‐subsidized PV‐based water pumps have emerged as a boon for such communities. But intermittent nature of solar irradiation and unavailability at night time poses a big challenge. To mitigate this challenge, the present article proposes a stand‐alone PV‐based induction motor‐driven water pumping system serving a dual‐head, that is, an overhead storage tank and ground level supply. A single‐stage three‐phase high‐gain resonant inverter (HGRI) is proposed for driving the induction motor. A back‐ended wide bandgap (WBG) device‐based boost converter is used to extract maximum power from PV by employing the MPPT algorithm. HGRI injects sinusoidal current to the induction motor while operating it through PV power matched modified V/f control algorithm, thus minimizing the torque ripple. HGRI coupled with boost converter provides a high‐gain voltage boost at the output; enabling wide input voltage operation, which increases the operability of the system in high as well as low irradiation level. The practicality of the system is validated on a laboratory‐developed hardware test bed with a 1.5HP induction motor. [ABSTRACT FROM AUTHOR]

An enhanced DC–DC converter is proposed in this paper, based on the combination of the Cuk converter and single-ended primary-inductor converter (SEPIC). This converter uses a single switching node which is common to both Cuk and SEPIC energy transfer stages. The converter uses only one switch, yet provides dual outputs in the form of a bipolar DC bus with a common ground. Since the switch is grounded, a simple, non-isolated gate driver may be used. The proposed converter uses integrated magnetic cores to couple the input and output inductors, which significantly reduces the input current ripple. The new converter is referred to as the Coupled-Inductors Combined Cuk-SEPIC (CI-CCS) converter. [ABSTRACT FROM AUTHOR]

Single-stage high-gain inverters have recently gained much research focus as interfaces for inherent low voltage DC sources such as fuel cells, storage batteries, and solar panels. Many impedance-assisted inverters with different input stage configurations have been presented. To decrease passive component sizes, these inverters operate at high-frequency switching. The high-frequency switching optimizes the passive component sizes but introduces many challenges in the form of high-frequency inductor design, control complexity, high-frequency gate driver requirements, high semiconductor losses, and electromagnetic interferences. This article proposes a novel fundamental frequency switching operation for the conventional voltage source inverters (VSI) to operate as a single-stage high-gain inverter. As the novel operational strategy changes the behavior of conventional VSI from buck inverter to a boost inverter, it is hereafter termed as a novel inverter. By virtue of the operation strategy, switches withstand peak inverse voltage (PIV) equal to DC link voltage, unlike other impedance assisted boost inverters where PIV across switches is the amplified DC voltage. The proposed inverter can invert low-level DC voltage to high voltage AC with low total harmonic distortion (THD) in a single stage without the help of any external filter. A novel quarter-wave symmetric phase-shift controller is proposed for variable voltage and frequency control of proposed inverters tuned by a back-propagation thin-plate-spline neural network (BPTPSNN). Mathematical analysis with experimental validation is presented. Experimentation is carried out on a prototype of 2 kW for single-phase resistive load, induction motor, and non-linear loads. [ABSTRACT FROM AUTHOR]