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This study provides a comparative analysis of feasible architectures of Power Pulsating Buffer (PPB) as an actively controlled energy storage solution alternative to the electrolytic capacitors in a single‐stage isolated, single‐phase 120 V AC 60Hz grid‐connected photovoltaic (PV) microinverter for a 400 W rated system with 20–40 V input range. The comparison encompasses key factors including energy density, volume reduction, efficiency, frequency operation, and system stability. The findings shed light on the primary advantages and disadvantages of the buck‐ and boost‐derived PPB under study. The results indicate that the boost PPB exhibits enhanced stability, a more compact design, and higher power efficiency compared to the buck PPB. However, for low switching frequency operations, the buck PPB proves to be more effective in mitigating DC port voltage ripple and ensuring controller over microinverter load variation. [ABSTRACT FROM AUTHOR]

To simultaneously solve the problems of the state-of-charge (SOC) equalization and accurate current distribution among distributed energy storage units (DESUs) with different capacities in isolated DC microgrids, a multi-storage DC microgrid energy equalization strategy based on the hierarchical cooperative control is proposed. In the primary control layer, the link between the droop coefficient and SOC is established through a logarithmic function, and the droop coefficient is adaptively adjusted according to the SOC value in order to achieve fast SOC equalization. In the secondary control layer, by designing a coordinated state factor, only one PI controller is required to eliminate the influence of the line impedance on the accurate distribution of the output current and the DC bus voltage drop. In the communication layer, local nodes only need to communicate with neighboring nodes without the need for a central controller, and the dynamic consistency algorithm is used to obtain the average value information about the energy storage system (ESS). Finally, the feasibility and effectiveness of the proposed control strategy are verified by experimental analysis on the DC microgrid hardware-in-the-loop experimental platform. [ABSTRACT FROM AUTHOR]

Combination of Wireless Power Transfer (WPT) and artificial intelligence (AI) offers huge prospects for several industries such as consumer electronics. This study looks at the recent developments in WPT, particularly concerning AI-improved efficiency, range and reliability. Data based on experiments show a significant improvement in the efficiency of information transfer where AI is used, with rates up to 25% higher than those using traditional ways. Additionally, advanced maintenance forecasting algorithms improve system availability by cutting down on 30% of downtimes in real-life applications of AI technology. The study also looks at the scope for further research, including emergence of distributed AI for autonomous WPT network, and quantum computing for improving algorithms. The study concludes that the convergence of WPT and AI could enhance the efficiency and robustness of power transfer systems, and hence it is essential to continue the investigation in this interdisciplinary field to advance existing technology and discover novel possibilities. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accurate prediction of junction temperature is crucial for the efficient thermal design of silicon nano-devices. In nano-scale semiconductor devices, significant ballistic effects occur due to the mean free path of phonons comparable to the heat source size and device scale. We employ a three-dimensional non-gray Monte Carlo simulation to investigate the transient heat conduction of silicon nanofilms with both single and multiple heat sources. The accuracy of the present method is first verified in the ballistic and diffusion limits. When a single local heat source is present, the width of the heat source has a significant impact on heat conduction in the domain. Notably, there is a substantial temperature jump at the boundary when the heat source width is 10 nm. With increasing heat source width, the boundary temperature jump weakens. Furthermore, we observe that the temperature excitation rate is independent of the heat source width, while the temperature influence range expands simultaneously with the increase in heat source width. Around 500 ps, the temperature and heat flux distribution in the domain stabilize. In the case of dual heat sources, the hot zone is broader than that of a single heat source, and the temperature of the hot spot decreases as the heat source spacing increases. However, the mean heat flux remains unaffected. Upon reaching a spacing of 200 nm between the heat sources, the peak temperature in the domain remains unchanged once a steady state is reached. These findings hold significant implications for the thermal design of silicon nano-devices with local heat sources. [ABSTRACT FROM AUTHOR]

Membrane fouling inevitably occurs during nanofluidic reverse electrodialysis. Herein, the impact of multi-fouling on the energy conversion performance of negatively charged conical nanochannels under asymmetrical configurations is systematically investigated. The results reveal that in Configuration I, where a high-concentration solution is applied at the tip side, at small concentration ratios, multiple foulings reduce the electric power. In Configuration II, where a low-concentration solution is applied at the tip side, multiple foulings near the base side contribute to the electric power. Any fouling that formed near the low-concentration entrance diminished the electric power and energy conversion efficiency. Multi-fouling lowered the electrical power consumption by 69.27% and 99.94% in Configurations I and II, respectively. In Configuration I, the electric power first increased with increasing fouling surface charge density, reached its maximum value, and thereafter decreased. In Configuration II, the electric power first decreased with increasing fouling surface charge density, reached its minimum value, and thereafter increased. Large negative or positive charge densities of fouling contribute to the electric power and energy conversion efficiency. [ABSTRACT FROM AUTHOR]

In recent years, low-dimensional metal halides have emerged as promising, optoelectronic materials. In particular, low dimensional Cu(I)-based perovskite halides have broad prospects in X-ray and gamma ray detection applications. However, conventional scintillators based on perovskites are still suffering from phase segregation, low yield, and toxicity issues. In this work, we introduced an organometallic Sb compound to enhance the scintillation properties of inorganic perovskite Cs3Cu2I5@PMMA via an in situ doping strategy. Cs3Cu2I5:Sb@PMMA scintillators possess a high attenuation coefficient of ionizing radiation, and the flexible films can meet the requirement of more complex imaging conditions. They also have high stability towards moisture and oxygen. Besides, the PMMA matrix enhances the stability of Cs3Cu2I5:Sb@PMMA scintillators, resulting in remarkable radiation resistance even under continuous X-ray irradiation. The Sb-enhanced Cs3Cu2I5:Sb@PMMA scintillators also resulted in improved light yield and exhibited excellent performance for X-ray imaging and single photon detection under 241Am irradiation. The above results fully demonstrate the excellent application potential of Cs3Cu2I5:Sb@PMMA for ionizing radiation detection and pave the great avenue of metal halide perovskites for commercialization. [ABSTRACT FROM AUTHOR]

The issues of health assessment and lifespan prediction have always been prominent challenges in the large‐scale application of lithium‐ion batteries (LIBs). This paper reviews the multiscale modeling techniques and their applications in battery health analysis, including atomic scale computational chemistry, particle scale reaction simulations, electrode scale structural models, macroscale electrochemical models, and data‐driven models at the system level. Multiscale modeling offers a profound insight into material behavior and the aging process of batteries, thereby providing a valuable reference for both estimation and management strategies of battery state of health. To extend the battery lifespan, the utilization of artificial intelligence for material discovery and manufacturing process optimization, the implementation of end‐cloud collaborative battery management systems, and the design of a multiscale simulation integration platform are considered. A management framework aimed at extending battery life is further proposed. This framework offers a promising roadmap for addressing health analysis challenges in LIBs, ultimately leading to more reliable, efficient, and durable solutions for next‐generation batteries. [ABSTRACT FROM AUTHOR]

Compared to the traditional thermal power generation, new energy sources, such as wind and photovoltaic systems, are more vulnerable to the effects of non-ideal power grids due to their limited capacity. This susceptibility can jeopardize the safe operation of power equipment, degrade power output quality, and lead to non-compliance with grid-connected specifications. The LCL-type grid-connected inverter is a typical nonlinear system that weakens the controllability of the grid-connected energy. To address these challenges, this study employs feedback linearization theory to transform the inverter into a standard linear system. Subsequently, it utilizes linear system methodologies to develop robust control laws, ultimately introducing a multifunctional multiplexing control strategy for grid-connected inverters based on feedback linearization and Hamilton-Jacobi-Issacs inequality. Simulation results demonstrate that this multi-functional strategy outperforms traditional grid- connected inverter control schemes, effectively mitigating issues related to low short-circuit ratios, voltage fluctuations, imbalances, harmonics, and other non-ideal grid conditions. Furthermore, it significantly expands the system's adaptability to varying weak grid impedances. [ABSTRACT FROM AUTHOR]

In the paper, a discrete dynamic model of a full-bridge resonant converter with a symmetrical operating mode has been obtained, which describes the resonant converter as a transfer link with an supply voltage input side and a load current output side. The dynamic model is based on a linear mathematical model of the resonant converter built according to the superposition principle. The structure of the resonant converter with the processes outline function is given and analyzed. The structure of the discrete dynamic model of the resonant converter of the nth order is presented. It is proved that the transfer function of the discrete dynamic model for the outline function can be determined by the transfer function of the continuous system. The resulting dependencies describing the discrete transfer functions of the resonant converter are used to obtain the discrete dynamic model of the double-circuit transformer resonant converter in a synchronous rectifier. For this, the sequence of actions is defined: definition of the transfer function of the continuous dynamic model; obtaining the system of equations in vector-matrix form describing electromagnetic processes in the converter; definition of the system of discrete equations; definition of the transfer function of the circuit. The obtained theoretical results were verified by means of simulation modeling of the considered double-circuit resonant converter. The proposed dynamic model makes it possible to analyze the influence of instability and low frequency fluctuations of the supply voltage of the resonant converter on the output values. The presented results can be used in the development and improvement of single- or multi-circuit bridge high-frequency resonant converters as the secondary power sources and converters used in ship demagnetization systems. References 25, figures 8, tables 2. [ABSTRACT FROM AUTHOR]

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ternary copper halides, such as Cs3Cu2I5, as an emerging class of nontoxic alternatives to lead halide perovskites, have drawn extensive attention in the X-ray detection field due to their efficient self-trapped exciton emissions. However, the light yield far below the theoretical limit seriously hinders the high-resolution X-ray detection application of copper halide scintillators. Herein, Cs3Cu2I5:K+ scintillation films and single crystals with enhanced photoluminescence (PL) and radiation luminescence (RL) were first obtained by adjusting the doping concentration of K+ ions in the 0–8 at% range. The substitution of Cs+ by doping K+ compacted the adjacent [Cu2I5]3− dimer groups, resulting in a stronger exciton–photon coupling strength. Therefore, Cs3Cu2I5:K+ single crystals exhibited a stronger RL emission under X-ray excitation, and their light output was about 49.6% higher than that of the pure Cs3Cu2I5, with an accelerated scintillation decay time (330 to 241 ns). Benefiting from these advantages, X-ray detectors based on hydrophobic polymethyl methacrylate (PMMA)-coated Cs3Cu2I5:K+ flexible films could deliver a higher X-ray imaging resolution of 11.7 lp mm−1@MTF = 0.2 in comparison with the commercial gadolinium oxysulfide (GOS)-based detectors (6.2 lp mm−1@MTF = 0.2). This work provides insights for the design of metal halides for use in low-cost and high-resolution flexible X-ray imaging systems. [ABSTRACT FROM AUTHOR]

In this work, an empirically derived multi-domain model of a light-emitting diode (LED) luminaire is proposed. The optical, electrical, and thermal characteristics of LEDs are obtained from the data sheets provided by manufacturers. Both transient and steady-state performance of LED luminaire were realized theoretically and validated against experimental findings from earlier investigations. The difficulties encountered in creating an ideal LED luminaire are discoursed and examined. Most of the studies on LED luminaires described in prior works ignored the influence of luminaire housing and optics on the thermal management of the luminaire. Knowledge of thermal time constants of LED luminaires is important, as they decide the rate of luminous flux decay when LED lighting systems are used for long periods of operation. Thermal time constants also decide the time taken by the LED junction to reach steady state with its surrounding. From the study it is inferred that the increase in junction temperature and deterioration of luminous flux is controlled by the product of the single most dominant thermal resistance from the junction to a point along the heat conduction path and sum of all the downstream thermal capacitances. This is true as in most cases LED device thermal capacitance is very less related to the thermal capacitance of the heat-sink, hence the product of single most dominant thermal resistance and thermal capacitance of heat-sink decide the rate of rising of junction temperature or luminous flux deterioration. [ABSTRACT FROM AUTHOR]

The research object in this research is the copper winding in the WPT system which characteristics will be observed after being coated with a concentration of curcumin. From the experiment of coating the curcumin concentration:H2O on the surface of the copper coil, it shows that there is an influence of physical phenomena from the curcumin concentration material. The strength of the magnetic field (B) and electric current (I) increased after the process of coating the concentration of curcumin:H2O on the copper coil for 0–5 hours. A coil wound with an electric current produces a strong magnetic field (B1), while the curcumin compound (C20H21O6) contains two aromatic benzene rings which produce a strong magnetic field on 6p (B2). Measuring the magnetic field strength using a Gauss meter after the curcumin concentration coating process showed an increase in the magnetic field strength and electric current. Assuming the equation for magnetic field strength B = B1+B2. Increasing the strength of the magnetic field and electric current in the copper winding of the wireless power transfer (WPT) system will affect the power efficiency of the copper windings L1 (transceiver) and L2 (receiver). The process of coating curcumin on a layer of copper to determine the electromechanical effect of curcumin. Utilization of curcumin as an alternative to increase power efficiency in WPT and increase conductivity in copper windings [ABSTRACT FROM AUTHOR]

The paper presents a simple method of measuring the luminous flux value dedicated to LED light sources. This method uses information about a spatial radiation pattern of the lighting source under test and the results of illuminance measurements at the axis of this source. The method is described and the results of the measurements obtained using this method and the classical method are compared and discussed. Tests have been carried out for LED modules of different geometries. The measurement error of the considered method is analysed. [ABSTRACT FROM AUTHOR]

Introduction. Photovoltaic (PV) systems gained immense attraction in the recent years since it produces electricity without causing environmental pollution through direct conversion of solar irradiance into electricity. Solar PV panels produce DC power. The magnitude of this DC power varies with temperature and irradiance of the sun rays. The DC supply from solar panels can be regulated using DC-DC converter and then can further be converted into the desired AC voltage by means of a voltage source inverter before being fed to an induction motor (IM). The speed and torque of an IM, fed from PV arrays, can vary due to the variation in the output power of the panels. Goal of this work is to improve the dynamic performance and reduce the torque ripple of Cuk converter-inverter fed IM drive system. The novelty of the current work proposes interleaved Cuk converter between solar PV DC source and the inverter. Purpose. To provide continuous current using an interleaved Cuk converter to the IM drive and in turn to reduce the torque ripple in IM. Methodology. Introduced an interleaved Cuk converter which is a blend of Cuk converters connected in parallel with each other between solar PV arrays and IM drive system. Originality. Simulation results are obtained for Cuk converter and interleaved Cuk converter fed IM drive by means of MATLAB. The hardware setup for the same IM systems is developed. Practical value. Simulation and hardware results are coincided with each other and it is subject from the simulation and hardware results that the interleaved Cuk converter-inverter fed IM system produced results superior than the Cuk converter inverter fed IM drive system. References 25, table 2, figures 22. [ABSTRACT FROM AUTHOR]