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Developing a fluidic platform that combines high-throughput with reconfigurability is essential for a wide range of cutting-edge applications, but achieving both capabilities simultaneously remains a significant challenge. Herein, we propose a novel and unique method for droplet manipulation via drawing surface charge graphics on electrode-free papers in a contactless way. We find that opposite charge graphics can be written and retained on the surface layer of porous insulating paper by a controlled charge depositing method. The retained charge graphics result in high-resolution patterning of electrostatic potential wells (EPWs) on the hydrophobic porous surface, allowing for digital and high-throughput droplet handling. Since the charge graphics can be written/projected dynamically and simultaneously in large areas, allowing for on-demand and real-time reconfiguration of EPWs, we are able to develop a charge-graphic fluidic platform with both high reconfigurability and high throughput. The advantages and application potential of the platform have been demonstrated in chemical detection and dynamically controllable fluidic networks. [ABSTRACT FROM AUTHOR]

Plastic has significant negative consequences for the environment and human health, demanding greener alternatives. Lignocellulose is a sustainable biomass material, and its paper has been considered as a potential material to replace plastics. Micro-nano lignocellulose, derived from natural plants, possesses a small size and abundant hydrogen bonding capacity. However, there is no clear explanation for the interactions between lignin and micro-nano cellulose, and little understanding of how the interaction can affect the papers' structure and optical properties. Electrostatic potential calculation is a reliable tool to explain non-covalent interactions, and can explore the binding between lignin and micro-nano cellulose. In this paper, kenaf – a non-wood fiber raw material – was employed to prepare micro-nano lignocellulose. The resulting slurry facilitated the production of transparent paper via a simple casting method. The prepared transparent micro-nano paper exhibited high transparency (~90 %), UVA resistance (~80 %), and hydrophobicity (~114°). More importantly, the electrostatic potential calculation demonstrates the inherent relationship between structure and performance, providing practical knowledge for constructing film materials. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel colorimetric-fluorescent dual-mode sensing sensor JT5 was successfully synthesized, and exhibited red fluorescence enhancement effect and red colorimetric sensing, and excellent applicability through solid-state fluorescent strips and biological imaging experiments on zebrafish to highly sensitive monitoring Sn4+ ions. [Display omitted] • A novel and effective rhdamine B-based sensor JT5 successful development. • JT5 can serve as a fluorescent and colorimetric on-off sensor for Sn4+. • The sensor JT5 was successfully studied using fluorescence and colorimetric of the test strips. • Biomaging experiments for the sensor JT5 were conducted on zebrafish using a confocal microscope. A novel colorimetric-fluorescent dual-mode chemosensor (JT5) based on rhodamine B has been produced for monitoring Sn4+ in the DMSO/H 2 O (4:1, v/v) medium. It has high sensitivity, a low detection limit, a short response time (1 s) and high stability, and can still be maintained after two weeks with the red dual fluorescence/ colorimetric response. Enhancement of red fluorescence (591 nm) and red colorimetric (567 nm) response of JT5 by Sn4+ addition. The electrostatic potential of the sensor JT5 molecule was simulated to speculate on the sensing mechanism, and the IR, mass spectrometry and 1H NMR titration were utilized to further demonstrate that JT5 was coordinated to Sn4+ with a 1:1 type, the rhodamine spironolactam ring of JT5 opens up to form a penta-membered ring with Sn4+, meanwhile, its system may have chelation enhanced fluorescence (CHEF) effect. In addition, theoretical calculations were carried out to give the energy gaps of JT5 and [ JT5 + Sn4+] as well as to simulate the electronic properties of the maximal absorption peaks. Notably, the sensor JT5 was successfully applied to monitoring Sn4+ in zebrafish, and the JT5 -loaded filter paper provided a solid-state platform for detecting Sn4+ by both naked eye and fluorescent methods. In summary, this work contributes to monitoring Sn4+ in organisms and solid-state materials and promotes understanding of Sn4+ functions in biological systems, environments, and solid-state materials. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the traditional short-circuit current calculation method is not applicable to Distributed Generation (DG) accessing the distribution network, the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG. Firstly, the output characteristics of DG in the process of low voltage ride through are analyzed, and the equivalent output model of DG in the fault state is obtained. Secondly, by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates, the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network. Then, iterative computation is performed within each partition, and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network, which solves the problems of long iteration time and large calculation error of traditional short-circuit current. Finally, a 62-node real distribution network model containing a high proportion of DG access is constructed on MATLAB/Simulink, and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper, and its calculation speed is improved by 48.35% compared with the global iteration method. [ABSTRACT FROM AUTHOR]

Industrial wireless mesh networks (WMNs) have been widely deployed in various industrial sectors, providing services such as manufacturing process monitoring, equipment control, and sensor data collection. A notable characteristic of industrial WMNs is their distinct traffic pattern, where the majority of traffic flows originate from mesh nodes and are directed towards mesh gateways. In this context, this paper adopts and revisits a routing algorithm known as ALFA (autonomous load-balancing field-based anycast routing), tailored specifically for anycast (one-to-one-of-many) networking in WMNs, where traffic flows can be served through any one of multiple gateways. In essence, the scheme is a hybrid-type routing strategy that leverages the advantages of both back-pressure routing and geographic routing. Notably, its novelty lies in being developed by drawing inspiration from another field, specifically from the movement of charges in an electrostatic potential field. Expanding on the previous work, this paper explores further in-depth discussions that were not previously described, including a detailed description of the analogy between an electrostatic system and a WMN system based on precise mapping perspectives derived from intensive analysis, as well as discussions on anycast, numerical methods employed in devising the ALFA scheme, its characteristics, and complexity. It is worth noting that this paper addresses these previously unexplored aspects, representing significant contributions compared to previous works. As a completely new exploration, a new scheduling strategy is proposed that is compatible with the routing approach by utilizing the potential-based metric not only in routing but also in scheduling. This assigns higher medium access priority to links with a larger potential difference. Extensive simulation results demonstrate the superior performance of the proposed potential-based joint routing and scheduling scheme across various aspects within industrial WMN scenarios. [ABSTRACT FROM AUTHOR]

Dedicating more attention to renewable energies and power electronic improvements results in increased direct current microgrids (DC MGs) application. However, DC MGs have some challenges with voltage adjustment and power sharing. To do so, a two-layer hierarchical control structure, including a new fully distributed secondary control strategy and conventional primary droop control method, is proposed and employed in this paper to share power and swiftly adjust the voltage accurately. Indeed, a distributedaveraging proportional-integral (DAPI) secondary control strategy is introduced. Another problem in DC MGs is the existence of constant power loads (CPLs), which may result in instability. To overcome the problems caused by CPLs, a term based on the output voltage of CPL is added to the proposed DAPI to prevent instability. The required control inputs are obtained using localized data of the DC bus and their neighbor's secondary control inputs inspired by cooperative control. Besides, this strategy needs no knowledge of the microgrid topology, which enhances flexibility. For validating the proposed DAPI strategy in DC MGs, an islanded DC MG is simulated in the MATLAB/SIMULINK software. Comparing the results with those obtained from another existing method proves the performance of the proposed DAPI controller under different scenarios of plug-and-play, communication failure, and load changes. [ABSTRACT FROM AUTHOR]

In this paper, a new structure for a 1-bit full adder is proposed based on dynamic logic methodology, which utilises pass transistors. The clocking operation falls into two phases. The clocking operation consists of a pre-discharged cycle, during which pseudo capacitors are reset to zero when the clock signal is high, and an evaluation cycle, during which the circuit outputs the adder function when the clock signal is low. The circuit uses a combination of 12 pass-transistors to better implement the full adder logic function with the maximum of a NMOS threshold voltage drop. Moreover, the circuit has no direct connection to the power-supply node and so this can possibly save the power dissipation. Our new adder outperforms other 1-bit full adder structures in terms of power-delay factor, according to simulation results. [ABSTRACT FROM AUTHOR]

Carrier phase‐shifted sine pulse width modulation is a common modulation strategy for medium‐ and low‐voltage cascaded H‐bridges (CHB). This paper proposes a novel jittered‐carrier phase‐shifted sine pulse width modulation (JCPS‐SPWM) to reduce the total harmonic distortion (THD) of the converter. It makes the carrier jitter regularly while the total switching times remain unchanged, which reduces the THD of the bridge arm voltage and current by moving the low‐order output harmonics of the bridge arm voltage and current to filterable high‐order harmonics. Since the total number of switching times remains unchanged, this modulation strategy will not cause any increase in switching loss. A seven‐level CHB simulation model and an experimental prototype are built to verify the effectiveness of the approach. The results show that harmonic content can be reduced by 47.5% compared with the traditional method, thus verifying the effectiveness of the JCPS‐SPWM. [ABSTRACT FROM AUTHOR]

Planning maintenance of medium voltage overhead lines is one of the most important issues in the studies on power distribution network, which will prevent and reduce unwanted interruption. In this paper, long‐term maintenance of medium voltage networks was planned by multi‐objective function, including an extended mixed‐integer linear model to optimize costs, energy not supplied (ENS), and average interruption duration index (SAIDI). In addition, the uncertainty about the annual growth rate of the load, the increase in the cost of goods and services and the increase in the selling price of energy as well as various constraints are all included in the desired objective function, which is one of the main innovations of this paper compared to other published studies. To apply the uncertainties, information gap decision theory (IGDT) has been used, and to solve the objective functions, LP‐Metric method has been used. The proposed method was implemented on the standard 11‐bus RBTS network by MATLAB and GAMS. The results showed that three different long‐term maintenance plans proposed here lead to the optimization of the annual maintenance costs of network, reduction in ENS and interruption, and increase in the reliability of the network based on the uncertainty of each feeder. [ABSTRACT FROM AUTHOR]

This paper presents the first implementation of a coupling between advanced wavefunction theories and molecular density functional theory (MDFT). This method enables the modeling of solvent effect into quantum mechanical (QM) calculations by incorporating an electrostatic potential generated by solvent charges into the electronic Hamiltonian. Solvent charges are deduced from the spatially and angularly dependent solvent particle density. Such a density is obtained through the minimization of the functional associated with the molecular mechanics (MM) Hamiltonian describing the interaction between the fluid particles. The introduced QM/MDFT framework belongs to QM/MM family of methods, but its originality lies in the use of MDFT as the MM solver, offering two main advantages. First, its functional formulation makes it competitive with respect to sampling-based molecular mechanics. Second, it preserves a molecular-level description lost in macroscopic continuum approaches. The excited state properties of water and formaldehyde molecules solvated into water have been computed at the selected configuration interaction (SCI) level. The excitation energies and dipole moments have been compared with experimental data and previous theoretical work. A key finding is that using the Hartree–Fock method to describe the solute allows for predicting the solvent charge around the ground state with sufficient precision for the subsequent SCI calculations of excited states. This significantly reduces the computational cost of the described procedure, paving the way for the study of more complex molecules. [ABSTRACT FROM AUTHOR]

This paper introduces a 17-bus 500 kV test system intended for transmission expansion planning (TEP) studies. The overhead lines used in the system are based on an actual 500 kV transmission line geometry. Although several test systems have been developed for various forms of power system analysis, few are specifically tailored for TEP studies at the transmission voltage level, as opposed to the distribution voltage level. Current test systems for TEP studies are limited to single loading conditions only for normal operating conditions, and the majority of these systems are intertwined with issues related to the energy market or devised specifically for integrating new generations and loads into the existing power systems. However, ensuring a test system satisfies both voltage drop and line loading criteria during both normal and all single contingency operations is crucial in TEP studies, and addressing these issues under contingency conditions poses notable challenges. Moreover, practical TEP scenarios involve varied loadings, including peak load and dominant loading (60% of peak load) scenarios, while the existing test systems are configured solely for single loading conditions. To address these technical gaps, this paper introduces the 17-bus test system operating at a transmission voltage level of 500 kV, meeting technical requirements under normal and all single contingency operations for both peak load and dominant load scenarios. Detailed specifications of the proposed test system and load flow analysis at both normal and contingency conditions for different loading conditions are presented. This test system serves as an invaluable resource for TEP studies. [ABSTRACT FROM AUTHOR]

In the electric vehicle wireless power transmission system, the high-frequency alternating magnetic field between the transmitter and receiver can have a certain impact on the health of living organisms and may even lead to lesions. In addition, metal foreign objects in an alternating magnetic field can cause their own heating or even cause fires due to the eddy current effect, so foreign object detection is an essential function in the wireless power transmission system of electric vehicles. In order to prevent metals and living organisms from entering the charging area and causing harm to the charging system and living organisms, this paper proposes a method for detecting living organisms and metal foreign objects. Firstly, the equivalent circuits for the detection systems of the living organism foreign objects and metal foreign objects are established, respectively, and the working theory of the detection system is analyzed by deriving equations. Secondly, the comb capacitor simulation model was constructed, and the comb capacitor electrode spacing, wire thickness, and capacitor spacing were designed based on the scale factor γ to explore the effects of the height and bottom area of the living organism's foreign object on the comb capacitor. We constructed a simulation model of the detection coil and designed the inner diameter D, the number of turns N, and the wire spacing S of the detection coil according to the scale factor β. An arrayed detection coil and comb capacitor combination mode is proposed to realize the function of the simultaneous detection of metal and living organism foreign objects, and a compensation capacitor is introduced to keep the detection system in a resonant state. Lastly, a platform for foreign object detection experiments was set up to detect metal screws and beef chunks compared to the detection area without foreign objects. Metal screws entering the detection area cause a 20% voltage drop in the detection circuit resistor, and beef chunks entering the detection area cause a 30% voltage drop in the detection circuit resistor, so the detection method is effective in detecting both metals and living organisms. The feasibility of the combined mode of arrayed detection coils and comb capacitors was verified. [ABSTRACT FROM AUTHOR]

Accurate quantification of the uncertainty in the mechanical characteristics of dielectric solids is crucial for advancing their application in high-precision technological domains, necessitating the development of robust computational methods. This paper introduces a Conditional Generation Adversarial Network Isogeometric Analysis (CGAN-IGA) to assess the uncertainty of dielectric solids' mechanical characteristics. IGA is utilized for the precise computation of electric potentials in dielectric, piezoelectric, and flexoelectric materials, leveraging its advantage of integrating seamlessly with Computer-Aided Design (CAD) models to maintain exact geometrical fidelity. The CGAN method is highly efficient in generating models for piezoelectric and flexoelectric materials, specifically adapting to targeted design requirements and constraints. Then, the CGAN-IGA is adopted to calculate the electric potential of optimum models with different parameters to accelerate uncertainty quantification processes. The accuracy and feasibility of this method are verified through numerical experiments presented herein. [ABSTRACT FROM AUTHOR]

Aiming at the solid oxide fuel cell (SOFC) applied to the ship DC microgrid in the face of pulse load disturbance is prone to make the SOFC voltage drop too large leading to the DC grid oscillation problem. In this paper, a stability criterion method for SOFC-Li battery DC system based on hybrid potential function is proposed. Firstly, a mathematical model of shipboard DC microgrid with SOFC-Li battery is established and the accuracy of the model is verified. Then, the stability criterion of the system based on the hybrid potential function under large disturbances is constructed. Subsequently, the effects of system stability under impulse load conditions were analysed under different parameters. Based on the constructed criterion, simulation verification of the stability boundary conditions of the SOFC system operating independently or jointly with a lithium battery system is carried out. The experimental results show that the proposed stability criterion and control strategy are effective in accurately predicting the system stability boundary. The experimental results verify the effectiveness of the proposed method in improving the stability of the system and provide a theoretical basis for further research on the dynamic characteristics of SOFC systems under complex load conditions. [ABSTRACT FROM AUTHOR]

This paper is concerned with a linear theory of thermopiezoelectricity in which the second gradient of the displacement, the second gradient of the electric potential and the second temperature gradient are included in the classic set of independent constitutive variables. The present paper is based on Green–Naghdi thermomechanics. The introduction of the entropy flux tensor leads to constitutive equations that depend on the second temperature gradient. The fundamental boundary-initial-value problems are formulated and the uniqueness of the solution is studied. Two applications of the theory are presented. We study the problem of a concentrated charge density acting in an unbounded region, as well as the effects of a concentrated heat source. [ABSTRACT FROM AUTHOR]

Pyroelectric materials, with piezoelectricity and pyroelectricity, have been widely used in infrared thermal detectors. In this paper, a modified first-order plate theory is extended to analyze a pyroelectric sensitive element structure. The displacement, temperature, and electric potential expand along the thickness direction. The governing equation of the pyroelectric plate is built up. The potential distributions with upper and lower electrodes are obtained under different supported boundary conditions. The corresponding numerical results of electric potential are consistent with those obtained by the three-dimensional finite element method. Meanwhile, the theoretical results of electric potential are close to that of experiments. The influence of supported boundary conditions, piezoelectric effect, and plate thickness are analyzed. Numerical results show that the piezoelectric effect reduces the electric potential. The thickness of the pyroelectric plate enhances the electric potential but reduces the response speed of the detector. It is anticipated that the pyroelectric plate theory can provide a theoretical approach for the structural design of pyroelectric sensitive elements. [ABSTRACT FROM AUTHOR]

During the modulation process of the VSI motor drive system, the nonlinear errors caused by the dead-time and conduction voltage drop will increase the phase current harmonic distortion and the torque ripple. To solve this problem, a novel dead-time free modulation scheme is proposed in this paper. In the non-zero crossing region of the phase current, the switching tube, whose body diode can provide a continuation path, is set as off-state, the driving signal is only implemented on another switching tube with the same bridge arm, and the errors caused by the conduction voltage drop and switching delay are compensated to the pulse duration. At the same time, to suppress the zero current clamp effect that exists near the zero crossing point of the phase current, another modulation scheme for the phase current crossing zero in advance is proposed, which avoids the complicated determination and calculation of the current polarity near the zero crossing point of the current. Both of the above modulation schemes eliminate the dead-time, and the switching principle is presented. In addition, to suppress the impact of the current ripple and high-frequency noise on the accuracy of the phase current detection, a second-order resonance digital filter without phase shift is introduced. Finally, compared to two deadtime compensation methods, the effectiveness and superiority of the proposed dead-time free modulation scheme are verified by the experimental results. [ABSTRACT FROM AUTHOR]

The paper presents summary data based on the results of laboratory studies and comprehensive industrial trials of a fundamentally new type of product in electrometallurgy — cores of graphitized electrodes developed at PWI of the NAS of Ukraine for DC and AC arc steel-melting furnaces of up to 50 t capacity. It is shown that during the last decades, the world production of steel has increased continuously, getting very close to 2 bln t per year. Approximately 30 % of this volume is produced in arc furnaces, and by the end of this decade it will reach 40 %. It is shown that the cored electrode arc has much lower specific current and power values in all the sections (cathode, column, anode) than the monolithic electrode arc. It was found that voltage drop in the core cathode spot is 2.3‒3.3 times smaller than in the monolithic electrode. Cored electrodes improve all the technical-economic characteristics of operation of DC and AC steel-melting furnaces. [ABSTRACT FROM AUTHOR]

Voltage source converter based high voltage direct current (VSC-HVDC) can participate in voltage regulation by flexible control to help maintain the voltage stability of the power grid. In order to quantitatively evaluate its influence on the voltage interaction between VSC-HVDC and line commutated converter based high voltage direct current (LCC-HVDC), this paper proposes a hybrid multi-infeed interaction factor (HMIIF) calculation method considering the voltage regulation control characteristics of VSC-HVDC. Firstly, for a hybrid multi-infeed high voltage direct current system, an additional equivalent operating admittance matrix is constructed to characterize HVDC equipment characteristics under small disturbance. Secondly, based on the characteristic curve between the reactive power and the voltage of a certain VSC-HVDC project, the additional equivalent operating admittance of VSC-HVDC is derived. The additional equivalent operating admittance matrix calculation method is proposed. Thirdly, the equivalent bus impedance matrix is obtained by modifying the alternating current (AC) system admittance matrix with the additional equivalent operating admittance matrix. On this basis, the HMIIF calculation method based on the equivalent bus impedance ratio is proposed. Finally, the effectiveness of the proposed method is verified in a hybrid dual-infeed high voltage direct current system constructed in Power Systems Computer Aided Design (PSCAD), and the influence of voltage regulation control on HMIIF is analyzed. [ABSTRACT FROM AUTHOR]

Data products relating to auroral arc systems are often sparse and distributed while ionospheric simulations generally require spatially continuous maps as boundary conditions at the topside ionosphere. Fortunately, all‐sky auroral imagery can provide information to fill in the gaps. This paper describes three methods for creating electrostatic plasma convection maps from multi‐spectral imagery combined with plasma flow data tracks from heterogeneous sources. These methods are tailored to discrete arc structures with coherent morphologies. The first method, "reconstruction," builds the electric potential map (from which the flow field is derived) out of numerous arc‐like ridges that are then optimized against the plasma flow data. This method is designed for data from localized swarms of spacecraft distributed in both latitude and longitude. The second method, "replication," uses a 1D across‐arc flow data track and replicates these data along a determined primary and secondary arc boundary while simultaneously scaling and rotating to keep the flow direction parallel to the arc and the flow shear localized at the arc boundaries. The third, "weighted replication," performs a replication on two data tracks and calculates a weighted average between them, where the weighting is based on data track proximity. This paper shows the use of these boundary conditions in driving and assessing 3D auroral ionospheric, multi‐fluid simulations. Plain Language Summary: The aurora, or northern and southern lights, are embedded within a complicated system of interacting electric fields, magnetic fields, and charged particles, the more energetic of which produce the lights themselves by exciting the neutral atmosphere. This brings about a 3D electric current system. These currents enter and exit the atmosphere along the Earth's magnetic field lines, and can only close their circuit between 80 and 150 km. This paper outlines the importance of simulating auroral arc systems in 3D and thus the need for generating continuous horizontal top‐boundary drivers for these simulations. This is difficult as the available data products are limited. This paper provides three methods for creating these boundary conditions using multi‐color, all‐sky auroral imagery in conjunction with approximately across‐arc plasma flow data tracks provided by spacecraft, sounding rockets, and/or radar measurements. Key Points: We provide three methods for developing ionospheric convection flow maps from limited data tracks in conjunction with auroral imageryMethods for generating distributed plasma flow surrounding auroral arcs can benefit from auroral arc information provided by all‐sky imageryModeling realistic auroral current closure needs drivers that vary along‐arc, across‐arc, and in altitude via electron precipitation spectra [ABSTRACT FROM AUTHOR]

In this paper, the effect of doping and nanostructuring on the electrostatic potential across the electrochemical interface between a transition metal oxide and a water electrolyte is investigated by means of the Poisson–Boltzmann model. For spherical nanoparticles and nanorods, compact expressions for the limiting potentials at which the space charge layer includes the whole semiconductor are reported. We provide a quantitative analysis of the distribution of the potential drop between the solid and the liquid and show that the relative importance changes with doping. It is usually assumed that high doping improves charge dynamics in the semiconductor but reduces the width of the space charge layer. However, nanostructuring counterbalances the latter negative effect; we show quantitatively that in highly doped nanoparticles the space charge layer can occupy a similar volume fraction as in low-doped microparticles. Moreover, as shown by some recent experiments, under conditions of high doping the electric fields in the Helmholtz layer can be as high as 100 mV/Å, comparable to electric fields inducing freezing in water. This work provides a systematic quantitative framework for understanding the effects of doping and nanostructuring on electrochemical interfaces, and suggests that it is necessary to better characterize the interface at the atomistic level. [ABSTRACT FROM AUTHOR]

A fast-switching low-loss field-stop insulated gate bipolar transistor with a dual control gate (DIGBT) of a semi-insulating polycrytalline silicon (SIPOS) material is proposed in this paper. Because the SIPOS has uniform high resistance, it has an approximate linear electric potential distribution. When DIGBT conducts, the higher electric potential on SIPOS causes the P-type drift region (P-drift) to generate an inversion layer of electrons, adjusting the number of carriers and making the generation of non-equilibrium carriers no longer dependent on the doping concentration in P-drift (Nd) but on the electric potential distribution on SIPOS. Therefore, it can solve the contradiction among the breakdown voltage, forward voltage drop [VCE(sat)], turn-off time (toff), and turn-off loss (Eoff) caused by the Nd. Through Technology Computer Aided Design (TCAD) simulation, the VCE(sat) of DIGBT is 30.6% lower than that of SJFS IGBT. Meanwhile, DIGBT reduces the toff by 62.8% while reducing the Eoff by 83.0% compared to SJFS IGBT. In addition, the static latch-up I–V and the forward biased safe operating area of the DIGBT have been significantly improved. This paper adjusts the number of carriers through the characteristics of SIPOS material, enabling the above-mentioned physical phenomena to be applied in insulated gate bipolar transistor power devices and achieving device performance breakthroughs. [ABSTRACT FROM AUTHOR]

This paper aims to analyze the inrush load current and develop an inrush current suppressor circuit optimized for a low-voltage DC (LVDC) distribution network. The connection of a substantial input capacitor in the DC load can induce a surge current, leading to significant issues in the LVDC distribution network, such as DC bus voltage drop and potential system damage. To address this issue, this paper presents the design of a voltage control system for a triple-active-bridge (TAB) converter in the LVDC distribution network, evaluating the need for the inrush current suppressor circuit. Control stability during the occurrence of the inrush current is analyzed using the small-signal model of the TAB converter. In addition, this paper proposes an inrush current suppressor circuit, presenting a design methodology to achieve the desired current suppression performance. Experiments are conducted on a laboratory-scale LVDC distribution network utilizing a 4-kW prototype converter to validate the performance of the suggested inrush current suppressor. [ABSTRACT FROM AUTHOR]

This paper presents a novel, state-of-the-art predictive control architecture that addresses the computational complexity and limitations of conventional predictive control methodologies while enhancing the performance efficacy of predictive control techniques applied to three-level voltage source converters (NPC inverters). This framework's main goal is to decrease the number of filtered voltage lifespan vectors in each sector, which will increase the overall efficiency of the control system and allow for common mode voltage reduction in three-level voltage source converters. Two particular tactics are described in order to accomplish this. First, a statistical approach is presented for the proactive detection of potential voltage vectors, with an emphasis on selecting and including the vectors that are most frequently used. This method lowers the computational load by limiting the search space needed to find the best voltage vectors. Then, using statistical analysis, a plan is presented to split the sectors into two separate parts, so greatly limiting the number of voltage vectors. The goal of this improved predictive control methodology is to reduce computing demands and mitigate common mode voltage. The suggested strategy's resilience is confirmed in a range of operational scenarios using simulations and empirical evaluation. The findings indicate a pronounced enhancement in computational efficiency and a notable diminution in common mode voltage, thereby underscoring the efficacy of the proposed methodology. This increases their ability to incorporate renewable energy sources into the electrical grid. [ABSTRACT FROM AUTHOR]

This paper introduces a new algorithm designed to address the challenge of distribution network reconfiguration, employing the tabu search metaheuristic in conjunction with the voltage drop concept. Distinguishing itself from existing methods, our proposed approach not only utilizes voltage drop for obtaining the initial solution but also introduces a novel technique for generating a candidate solution neighborhood. This method leverages both randomness and voltage drop, ensuring a smooth and steady descent during algorithm execution. The primary goal of our algorithm is to minimize active power losses within distribution networks. To validate its effectiveness, the proposed method underwent testing on three commonly referenced distribution systems: the 33-Bus, 69-Bus, and 94-Bus systems, widely acknowledged in the literature. A pivotal aspect of our work involves the synergy of the tabu search algorithm with a combination of both random and deterministic methods for generating neighbors. This strategic amalgamation plays a crucial role, enabling rapid execution while consistently yielding high-quality solutions. Additionally, the adoption of the electric distance method for generating the initial solution adds significant value, offering a commendable solution with minimal computational effort. Comparative assessments against other algorithms documented in the literature underscore the superior efficiency of our proposed algorithm. [ABSTRACT FROM AUTHOR]

The paper deals with the non-destructive experimental testing of the reinforced concrete beams under progressive corrosion. A series of experiments using electrical potential, ultrasound and low-frequency vibrations techniques are reported. Electrical potential and natural frequencies were used to characterise and monitor the corrosion process at its initial state. The P-wave velocity measurements were proved to be effective in quantitative assessment of the level of corrosion as it progresses. The possibility of early detection of damage using a proposed damage index and diagnostic framework is promising for possible applications in the non-invasive diagnostics of reinforced concrete elements. [ABSTRACT FROM AUTHOR]

Li-N2 batteries present a relatively novel approach to N2 immobilization, and an advanced N2/Li3N cycling method is introduced in this study. The low operating overpotential of metal–air batteries is quite favorable to their stable cycling performance, providing a prospect for the development of a new type of battery with extreme voltage. The battery system of Li-N2 uses N2 as the positive electrode, lithium metal as the negative electrode, and a conductive medium containing soluble lithium salts as the electrolyte. In accordance with its voltage-distribution trend, a variety of lithium-nitrogen molecule intermediates are produced during the discharge process. There is a lack of theoretical description of material changes at the microscopic level during the discharge process. In this paper, the first-principles approach is used to simulate and analyze possible material changes during the discharge process of Li-N2 batteries. The discharge process is simulated on a 4N-graphene anode substrate model, and simulations of its electrostatic potential, Density of States (DOS), HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) aspects confirm that the experimentally found Li3N becomes the final stabilized product of the Li-N2 battery. It can also be seen in the density of states that graphene with adsorption of 4N transforms from semiconducting to metallic properties. In addition, the differential charge also indicates that the Li-N2 material has a strong adsorption effect on the substrate, which can play the dual role of electricity storage and nitrogen fixation. [ABSTRACT FROM AUTHOR]

The main purpose of the paper is to show how a magnetoresistive (MR) element can work as a current sensor instead of using a Wheatstone bridge composed by four MR elements, defining the concept of a magnetoresistive shunt (MR-shunt). This concept is reached by considering that once the MR element is biased at a constant current, the voltage drop between its terminals offers information, by the MR effect, of the current to be measured, as happens in a conventional shunt resistor. However, an MR-shunt has the advantage of being a non-dissipative shunt since the current of interest does not circulate through the material, preventing its self-heating. Moreover, it provides galvanic isolation. First, we propose an electronic circuitry enabling the utilization of the available MR sensors integrated into a Wheatstone bridge as sensing elements (MR-shunt). This circuitry allows independent characterization of each of the four elements of the bridge. An independently implemented MR element is also analyzed. Secondly, we propose an electronic conditioning circuit for the MR-shunt, which allows both the bridge-integrated element and the single element to function as current sensors in a similar way to the sensing bridge. Third, the thermal variation in the sensitivity of the MR-shunt, and its temperature coefficient, are obtained. An electronic interface is proposed and analyzed for thermal drift compensation of the MR-shunt current sensitivity. With this hardware compensation, temperature coefficients are experimentally reduced from 0.348%/°C without compensation to −0.008%/°C with compensation for an element integrated in a sensor bridge and from 0.474%/°C to −0.0007%/°C for the single element. [ABSTRACT FROM AUTHOR]

DC railway electrification was deployed at the beginning of the 20th century in several countries in Europe. Today, this power system is no longer adapted to the demands of increased rail traffic. Due to the relatively low voltage level, the current consumed by the trains reaches several kAs. So, in the worst case, the locomotives cannot operate at their rated power due to the voltage drop along the contact line. Conventional solutions to reduce the voltage drop consist of increasing the cross-section of overhead lines or reducing the length of sectors by installing additional substations. Nevertheless, these solutions are expensive and not always feasible. The implementation of a Modular Battery Energy Storage System (MBESS) can be an alternative solution to reinforce the railway power supply. This paper first presents an MBESS based on elementary blocks associating Full-SiC Isolated DC-DC converter and battery racks. The electrical models of a railway sector and an elementary block are described, and simulations are performed considering real railroad traffic on two sectors of the French National Rail Network, electrified at 1.5 kV. The results show that the installation of an MBESS in the railway sector boosts the locomotive's voltage while also increasing overall system efficiency. [ABSTRACT FROM AUTHOR]

The inherent second harmonic power pulse in single-phase grid-connected rectifiers leads to a noticeable output voltage ripple and thus results in the degradation of the system. A novel second harmonic suppression control is introduced in this paper to address this issue. The key point of the proposed control lies in the real-time prediction of the phase-shifted full-bridge (PSFB) converter's desired duty cycle through accurate PSFB converter modeling. By accurately predicting the ideal duty cycle, the proposed control facilitates a significant enhancement in the control loop's gain specifically at the second harmonic frequency, thereby improving the overall system performance. To validate the theoretical analysis, a series of simulations and experiments were conducted. The results demonstrate the effectiveness of the proposed second harmonic suppression control in mitigating second harmonic output voltage ripple. [ABSTRACT FROM AUTHOR]

High frequency and high voltage switching converters utilizing wide bandgap semiconductors are gaining popularity thanks to their compactness and improved efficiency. However, the faster switching requirements gives rise to new challenges. A key issue is the increased oscillation of the drain–source voltage caused by the switching action of the complementary switch in the same phase or change of state of the other phase switches. The voltage stress caused by these oscillations can damage the switch. Furthermore, the high dv/dt during turning-on of one switch might result in false turn-on of the complementary switch due to the miller effect. In this paper, these issues are investigated in a T-type converter through analytical and experimental analysis. Based on the proposed analytical approach, simple and cost-wise solutions utilizing an optimum design of gate driver circuits and circuit layout modifications can be developed to cope with the aforementioned issues. A comprehensive analytical model of the converter with consideration of parasitic capacitances and inductances is developed. By performing sensitivity analysis on the model, the effect of the parasitic parameters on the drain–source voltage oscillation and gate–source voltage amplitude in case of false turn-on is studied. The validity of the model is then assessed through numerical simulations and experimental results. [ABSTRACT FROM AUTHOR]

The zero-relaxation limit of Euler–Poisson systems for ion dynamics in a slow time scale leads to drift-diffusion equations. This fact was justified in previous works. This paper concerns global error estimates between solutions of Euler–Poisson systems and that of drift-diffusion equations. In the proof, we use Sobolev inequalities and employ a multiplier related to the electric potential. [ABSTRACT FROM AUTHOR]

The distributed direct current (DC) power system relies heavily on the cascaded DC–DC converter that employs a common bus to connect multiple DC–DC converters. The first stage of the cascaded DC–DC converter is responsible for injecting power from a renewable source or a battery into the DC bus. Conversely, the second stage connects a load to the DC bus, creating a constant power load (CPL) that consumes constant power regardless of the supply voltage. This behavior often causes disturbances and instabilities, leading to unwanted oscillations that adversely impact the quality of the input current. To address this issue, this paper proposes an active current ripple-damping technique that extracts the fundamental of the inductor current. When combined with the super-twisting sliding mode control, this approach effectively mitigates input current ripples and enhances the stability of the CPL. The key to this approach is the sliding surface selection, which requires a cleaned inductor current from the second boost converter. Experimental results are provided to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper addresses the issue of LED short-circuit fault detection in signaling and lighting systems in the automotive industry. The conventional diagnostic method commonly implemented in newer vehicles relies on measuring the voltage drop across different LED branches and comparing it with threshold values indicating faults caused by open circuits or LED short circuits. With this algorithm, detecting cases of a few LEDs short-circuited within a branch, particularly a single malfunctioning LED, is particularly challenging. In this work, two easily implementable algorithms are proposed to address this issue within the vehicle's control unit. One is based on a mathematical prediction model, while the other utilizes a neural network. The results obtained offer a 100% LED short-circuit fault detection rate in the majority of analyzed cases, representing a significant improvement over the conventional method, even in scenarios involving a single malfunctioning LED within a branch. Additionally, the neural network-based model can accurately predict the number of failed LEDs. [ABSTRACT FROM AUTHOR]

The traditional medium-voltage distribution network fault location method uses mainly the voltage and current measurements of the medium-voltage side, which results in problems such as high installation costs at the measuring points and complicated postoperation and maintenance work. Therefore, a fault location idea based on the distributed measurement of low-voltage side voltage is proposed in this paper. First, the characteristic voltage is adaptively selected according to the fault type. Second, the suspected fault section is determined by comparing the characteristic voltage amplitude of each measuring point. Third, the fault section is located using the section unit characteristic voltage drop defined for each suspected fault section. Finally, fault distance estimation is achieved based on the voltage difference matrix and characteristic voltage analysis. This method achieves accurate fault distance identification based on the distribution difference of the characteristic voltage of the low-voltage side under the fault state. This work provides a new economical and practical idea for determining the fault locations of distribution networks. The effectiveness of this method is evaluated by considering a 10 kV distribution network in Guangdong Province built in PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]

As the information technology (IT) industry advances, embedded systems are being applied in various industrial sectors. With the expansion of application areas, there is a growing demand for high-precision, high-specification embedded systems, leading to the increased complexity of embedded software. Consequently, software errors can cause system malfunctions, resulting in accidents such as airplane crashes and the sudden acceleration of cars, leading to significant loss of life and property damage. Therefore, measures to ensure the safety and stability of increasing embedded systems malfunctions are necessary. This paper proposes a system that monitors the operation of target embedded systems in real-time and compares the extracted normal operation current/voltage patterns with the current/voltage data of a target embedded system (TES). It compares the operation data of the TES with automatically generated normal operation patterns by forcibly exposing them. It suggests algorithms for immediately detecting and efficiently recovering from the TES malfunctions. The proposed system applies two algorithms. (a) Monitoring TES current: When a malfunction is detected, a monitoring embedded systme (MES) resets the TES to restore normal operation. If malfunctions persist, it controls TES by using an algorithm to shut it down. Additionally, a proportional integral derivation (PID) control is applied to stabilize the current state. (b) Monitoring TES voltage: If a voltage drop occurs, the MES immediately stops the TES operation to minimize damage. The proposed algorithms were validated through experiments. For a normal TES consuming up to 95 mA, an error detection rate of 20% was applied. The TES was reset if it consumed over 114 mA. It was confirmed that the TES was stopped upon detecting the third malfunction. Regarding voltage, when the normal operating voltage of the system was around 5 V, if the TES operating voltage dropped below 4.3 V, it was detected as a malfunction, and the algorithm to stop the TES operation was validated. [ABSTRACT FROM AUTHOR]

As the electricity market expands with increasing demand, power systems are under more pressure to operate within secure limits. One way to ensure this is through load flow studies, which analyze the steady-state conditions of a power system under various load and generator scenarios. However, the complexity of power systems and the growing demand for electricity make it difficult to accurately predict and analyze power flow. The use of simulation software like electrical transient and analysis program (ETAP) can improve the accuracy and efficiency of load flow studies, but it still poses challenges such as complexity and lack of standardization in use. This paper focuses on voltage stability, voltage regulation, and the impact of capacitor banks on buses through load flow studies. Real data from four hydropower plants is used to analyze voltage drop, voltage regulation and power losses at each bus. The findings highlight the effectiveness of capacitor banks in improving voltage profiles and reducing power losses, thus proposing an optimized system design. These enhancements facilitate better planning, operation, and expansion of power systems, ensuring more reliable and efficient electricity supply. [ABSTRACT FROM AUTHOR]

In this paper, high-performance indium gallium oxide (IGO) thin-film transistor (TFT) with a double-gate (DG) structure was developed using an atomic layer deposition route. The device consisting of 10-nm-thick IGO channel and 2/48-nm-thick SiO2/HfO2 dielectric was designed to be suitable for a display backplane in augmented and virtual reality applications. The fabricated DG TFTs exhibit outstanding device performances with field-effect mobility (μFE) of 65.1 ± 2.3 cm2V−1 s−1, subthreshold swing of 65 ± 1 mVdec−1, and threshold voltage (VTH) of 0.42 ± 0.05 V. Both the (μFE) and SS are considerably improved by more than two-fold in the DG IGO TFTs compared to single-gate (SG) IGO TFTs. Important finding was that the DG mode of IGO TFTs exhibits the nearly temperature independent μFE variations in contrast to the SG mode which suffers from the severe remote Coulomb scattering. The rationale for this disparity is discussed in detail based on the potential distribution along the vertical direction using technology computer-aided design simulation. Furthermore, the DG IGO TFTs exhibit a greatly improved reliability with negligible VTH shift of − 0.22 V under a harsh negative bias thermal and illumination stress condition with an electric field of − 2 MVcm−1 and blue light illumination at 80 °C for 3600 s. It could be attributed to the increased electrostatic potential that results in fast re-trapping of the electrons generated by the light-induced ionization of deep level oxygen vacancy defects. [ABSTRACT FROM AUTHOR]

This paper presents application and tuning of the equilibrated residual method (ERM) of a posteriori error estimation for coupled electromechanical problems of direct, inverse and general piezoelectricity. In these three cases, either electric potential is induced by strains or strains appear due to the applied electric potential or both phenomena occur simultaneously. The mentioned ERM is assigned for the assessment of modeling and approximation errors of the numerical finite element solution. Such error values usually serve as indication for adaptive hierarchical modeling and adaptive mesh changes within thin and/or solid piezoelectric members so as to obtain the solution of assumed accuracy. [ABSTRACT FROM AUTHOR]

This paper deals with the control and performance improvement of parallel-operated voltage-source inverters (VSIs) controlled as virtual synchronous generators (VSGs). In publications regarding the parallel-operated VSGs, transmission lines are considered to be mainly inductive. However, less analytical works have been done regarding the control of paralleled VSGs in low-voltage grids with dominant resistive impedances. Once VSIs are controlled as VSGs in a microgrid with more resistive transmission lines, swing equation and system representation for the power-angle synchronization will change leading to a new control structure. Therefore, this paper deals with the control of parallel-operated converter-based VSGs in low-voltage grids with dominant resistive line impedances. In this way, the VSG representation, comprising the swing equation and V-P droop characteristic, for applications in highly resistive microgrids is presented, in which the swing equation and VSG frequency are related to reactive power. Then, the V-P droop characteristic is modified and an enhanced P-V droop characteristic for proper sharing of active power between the VSGs in highly resistive microgrids is proposed. Next, the VSG control is modified so that the R/X ratio at the VSG output increases and thus the decoupled control of active/reactive powers in relatively inductive cases is realized as well. [ABSTRACT FROM AUTHOR]

In this paper, a new GaSe/ZnS van der Waals heterostructure (vdWH) is devised and subjected to systematic analysis through first principles calculations in terms of its geometric, electronic and transport properties. The stability of GaSe/ZnS vdWH is verified through binding energy, phonon spectrum, and ab initio molecular dynamics (AIMD) simulation. Additionally, detailed calculations of plane average electron density difference and average electrostatic potential in the features of GaSe/ZnS vdWH interface are provided. The results show that GaSe/ ZnS vdWH comprises a heterostructure with a direct band gap of 2.19 eV and high carrier mobility. Among them, the electron mobility along the x direction reaches 1 394.63 cm²V-1⋅s-1, while the electron mobility along the y direction reaches 1 913.18 cm² ⋅V-1 ⋅s-1, demonstrating excellent performance and potential applications in electronic nano devices. [ABSTRACT FROM AUTHOR]

This paper presents a new conformal mapping method to solve 2D Laplace and Poisson equations in MOS devices. More specifically, it consists of an analytical solution of the 2D Laplace equation in a rectangular domain with Dirichlet boundary conditions, with arbitrary values on the boundaries. The advantages of the new method are that all four edges of the rectangle are taken into account and the solution consists of closed-form analytical expressions, which make it fast and suitable for compact modeling. The new model was validated against other similar methods. It was found that the new model is much faster, easier to implement, and avoids many numerical issues, especially near the boundaries, at the cost of a very small loss in accuracy. [ABSTRACT FROM AUTHOR]

Solar photovoltaics in Malta have increased substantially over the years, both at large scale and residential scale. The present installed capacity is already having a negative impact on Malta's' grid infrastructure, causing problems due to the reverse power flows (resulting from oversupply) and related issues such as voltage rise. This paper considers the integration of a low voltage regulator in a low voltage feeder in a semi‐rural area in Malta. A thyristor‐controlled transformer‐based low voltage regulator was modelled and simulated in MATLAB/Simulink using the PLECS blockset. Experimental results were also obtained via measurements of the voltage profiles at 70% of the actual low voltage feeder that showed several instances of over and under voltage events. The outputs obtained from the simulation model strongly agreed with those obtained from the field testing thereby validating the simulation models that were developed in this study. Results show that the voltage on the feeder was successfully regulated to around the nominal voltage of 240 V. The regulator failed to correct the voltage to within ±10% in one occurrence where the load demand and hence the voltage drop was too high. [ABSTRACT FROM AUTHOR]

2-(3-Bromophenyl)-1-(4-morpholinyl)ethanone belongs to one of morpholine derivatives. In this paper, 2-(3-bromophenyl)-1-(4-morpholinyl)ethanone was synthesized by a two-step synthesis method. In order to determine the structure of the target compound, FT-IR,1H NMR,13C NMR and MS were used for detection. Meanwhile, X-ray diffraction was used to detect the single crystal and obtain the crystal structure data of the target compound. The molecular crystal structure was compared with that determined by density functional theory. The frontier molecular orbitals and molecular electrostatic potential energy were used to further study the physical properties of the compounds. [ABSTRACT FROM AUTHOR]

The synthesis of gold(III) and gold(I)–gold(III) complexes with phosphide bridges is still a matter that requires solutions for their marked instability, in spite of the affinity of this metal in both oxidation states for phosphorous donor ligands. In the course of our studies, we realized that the presence of perhalophenyl groups of the type pentafluorophenyl or 3,5-dichlorotrifluorophenyl in the complexes gives rise to an increase in their stability that eases their isolation and structural characterization. In this paper, we describe two new fully characterized neutral compounds of this type to extend the knowledge on this family of compounds, [{Au(C6Cl2F3)2}2(µ-PPh2)2] (1) and [{Au(C6Cl2F3)2(µ-PPh2)2Au}2] (2). In this work, we analyze the role of the perhalophenyl groups in the stability of these complexes by using quantum chemical topology methodologies, specifically employing an analysis of the non-covalent interactions (NCIs) in real space and evaluating the electrostatic potential surfaces (ESP). Our findings reveal the existence of appreciable π-stacking interactions among the perhalophenyl and phenyl groups in both compounds, significantly contributing to the stability of the systems. [ABSTRACT FROM AUTHOR]

In the case of certain chemical compounds, especially organic ones, electrons can be delocalized between different atoms within the molecule. These resulting bonds, known as resonance bonds, pose a challenge not only in theoretical descriptions of the studied system but also present difficulties in simulating such systems using molecular dynamics methods. In computer simulations of such systems, it is often common practice to use fractional bonds as an averaged value across equivalent structures, known as a resonance hybrid. This paper presents the results of the analysis of five forms of C60 fullerene polymorphs: one with all bonds being resonance, three with all bonds being integer (singles and doubles in different configurations), one with the majority of bonds being integer (singles and doubles), and ten bonds (within two opposite pentagons) valued at one and a half. The analysis involved the Shannon entropy value for bond length distributions and the eigenfrequency of intrinsic vibrations (first vibrational mode), reflecting the stiffness of the entire structure. The maps of the electrostatic potential distribution around the investigated structures are presented and the dipole moment was estimated. Introducing asymmetry in bond redistribution by incorporating mixed bonds (integer and partial), in contrast to variants with equivalent bonds, resulted in a significant change in the examined observables. [ABSTRACT FROM AUTHOR]

In this paper, the electro-mechanical behavior of a flexoelectric nanobeam, considering the surface effect, is studied with an induced electric potential. Based on the modified strain gradient theory and Hamilton's variational principle, the governing differential equations of the nanobeam and the corresponding boundary conditions are obtained. The exact deflection solution of the flexoelectric nanobeam is derived from static bending. The relationship between the induced electric potential, including the surface effect, and the angle of the end of the cantilever beam is presented. Moreover, the characteristic equation of natural frequency is obtained by using a separate variable method under an open circuit with surface electrodes and an induced electric potential condition (OCI). The simulated results indicate the electro-mechanical response of the cantilever beam can be controlled by adjusting the flexoelectric coefficient, residual surface stress, and material length scale parameters of strain gradient theory. The free end of the beam with a platform phenomenon is also found by setting the appropriate parameters. The results also show that the residual surface stress and the ratio of beam thickness to material length scale parameters have a more significant effect on the effective frequency shift of the flexoelectric nanobeam. Therefore, considering the induced electric potential and surface effect is of great significance for the study of flexoelectric nanobeam sensors. [ABSTRACT FROM AUTHOR]

Permanent magnet (PM) motors are gaining prominence in subsea applications such as drilling, pumping, and boosting for oil and natural gas extraction. These motors are gradually replacing traditional induction motors. However, starting and operating PM motors at low speeds under heavy loads poses significant challenges. This is because of unknown initial rotor positions and resistive voltage drops due to the presence of a sinewave filter, transformer, and long cable. An unknown rotor position may result in temporary reverse speed, which may cause a loss of synchronism; therefore, initial rotor position estimation is preferable. Additionally, addressing the voltage drop issue requires careful voltage compensation to avoid transformer core saturation. In this paper, an enhanced V / H z starting of a PM motor is proposed with initial position detection (IPD) and voltage compensation to start the motor reliably with a heavy load. The proposed control method is verified with controller hardware in the loop (C-HIL) real-time simulation using a Typhoon HIL-604 emulator and a Texas Instruments TMS320F28335 digital signal processor (DSP) control card. [ABSTRACT FROM AUTHOR]

The fast-growing influence of grid-interfaced photovoltaic (PV) networks makes it necessary to adhere to grid-code (GC) regulations. These regulations mandate that PV systems inject active power both during and after the grid fault occurrence, as well as provide reactive current to the grid during voltage dips, in order to prevent power system stability concerns. In this context, two novel control schemes have been proposed in this paper for grid-connected photovoltaic networks that can support low-voltage ride-through (LVRT). The proposed control techniques have been demonstrated to be simple and efficient in the event of severe voltage dips, i.e., work up to a voltage drop of 90% of the nominal grid voltage. Our first approach involves an enhanced reactive current injection strategy that provides reactive power support to the power grid during voltage dips without any additional devices. The control structure is comprised of a voltage level estimator and a reactive current controller. The voltage level estimator obtains power grid voltage, while the reactive current controller computes active−reactive current commands. It is particularly noteworthy that the proposed scheme generates active current as much as possible according to the voltage dips and tracks the active current reference correctly, where conventional strategies fail to cope. The second control method for LVRT presented in this research work involves using hardware, specifically a crowbar. The use of a crowbar is the most straightforward method to provide support to the power system, bypassing over-current during voltage dips and keeping the current within the normal converter rating. The control strategies proposed in this paper are validated in MATLAB/Simulink under symmetrical and unsymmetrical severe voltage dips as well as grid voltage harmonics, and a detailed comparison study with a state-of-the-art PQ-based fault-ride-through controller has been conducted. [ABSTRACT FROM AUTHOR]

This paper proposes a system-in-package combination navigation chip. We used wire bonding, chip stacking, surface mount, and other processes to integrate satellite navigation chips, inertial navigation chips, microprocessor chips, and separation devices. Finally, we realized the hardware requirements for combined navigation in a 20 mm × 20 mm chip. Further, we performed a multi-physics simulation analysis of the package design. For antenna signals, the insertion loss was greater than −1 dB@1 GHz and the return loss was less than −10 dB@1 GHz. The amplitude of these noises of the signal between the MCU and the IMU was approximately 20%, and the maximum value of the coupling coefficient between signal lines on the top surface was 13.4174%. The ninth mode of the power plane yielded a maximum voltage of 55 mV, and all power delivery networks had a DC voltage drop of less than 2%. The highest temperature in the microsystem was approximately 42 °C. These results show that our design performed well in terms of signal, power, and thermal performance. [ABSTRACT FROM AUTHOR]