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An extensive revision of the IEEE C37.011 ‘Application Guide for TRV for AC High-Voltage circuit Breakers’ has been in process for the last four years. The main aim was to introduce the two- and the four- parameter description of the transient recovery voltage (TRV) as used in IEC Switchgear standards that have been introduced in the revisions of Standards C37.04 and C37.06. These two standards are being concurrently revised, but IEEE C37.011 provides the necessary explanations on TRV characteristic in advance. Non-specialist engineer users of the guide will better understand these standards. [ABSTRACT FROM AUTHOR]

Piezoelectric nanogenerators (PENGs) based on micro-fibre of polyvinylidene fluoride (micro-fibre polyvinylidene fluoride (PVDF)). Flexible nanogenerator was developed by addition nanoparticle composition. This PENG fabricated using micro-fibre PVDF/BaTiO3, which was deposited on paper interdigitate substrate by wire electrode free surface electrospinning method. The device from micro-fibre PVDF performed open-circuit voltage and short-circuit current of 13 mV and 380 nA recently. The device from composite material addition value of open-circuit voltage and short-circuit current of 528 mV and 661 nA recently. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various articles within the issue on topics including triple cascaded current-reuse low noise amplifier, power amplifier, and design micro power voltage reference.

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]

An international comparison of lightning and switching impulse voltage measuring systems was arranged and coordinated by the Helsinki University of Technology (MIKES-TKK), Espoo, Finland, between 1999 and 2002. The number of participants was 26, including the coordinator. This paper summarizes the results obtained by those eight National Metrology Institutes that participated in the comparison. A 400-kV transfer reference measuring system for measuring lightning impulse voltages was prepared by the coordinator. In addition, a 1-kV impulse voltage calibrator system, including calibrators for both standard lightning and switching impulses, was circulated. [ABSTRACT FROM AUTHOR]

We have successfully demonstrated a control device for viewing angle that enables switching two states between a wide-viewing angle and a narrow-viewing angle. It consists of a light-transmitting portion formed with an array of optical micro-rods and shielding/transmitting changeable portion designed with electrophoretic materials. The response time from the narrow-viewing to wide-viewing angle was one second at 20 V of applied voltage. [ABSTRACT FROM AUTHOR]

Flexible low-voltage electric-double-layer (EDL) thin-film transistors (TFTs) with a patterned indium–tin–oxide (ITO) channel are self-assembled on paper substrates by only one shadow mask at room temperature. The operation voltage is 1.5 V when a microporous \SiO2 solid electrolyte with large EDL capacitance is used as the gate dielectric. Such flexible TFTs operate in a full-depletion mode with a high mobility of 25.5 \cm^2/ \V\cdot\s, a low subthreshold swing of 0.16 V/decade, and a high current on/off ratio of \3 \times \10^5. The influence of mechanical bending to the electrical performance of the flexible EDL TFTs is investigated. A device simulator is used to simulate the electrical behavior, and a nice fitting to the experimental data is obtained. [ABSTRACT FROM AUTHOR]

In the past couple of years, the integration of electrical vehicles (EV) in the power system has been capturing the attention of many researchers, which has led to this being a frequently analysed topic in scientific papers and seminars. Some of the main parameters related to power quality that are observed, while integrating EVs, are voltage variations and voltage unbalance. The low-voltage rural network, of a small settlement located on the outskirts of Zavidovici, has been modelled for the purpose of this paper. Several cases were considered. As the first base case, an analysis was performed when there were no connected vehicles in the network, then the case with 20% penetration, 35% penetration, and 80% vehicle penetration. Practical analysis was done in DIgSILENT Power Factory software. It has been concluded that electrical vehicles cause a voltage drop in the network, while at the same time causing an increase in voltage unbalances. [ABSTRACT FROM AUTHOR]

The state of the oil-paper insulation is a key factor for assuring a reliable operation of power transformers. Recovery voltage measurement is one of the methods utilized to estimate the polarization spectrum. Analysis of the polarization spectrum is used to evaluate the condition of the insulation with respect to moisture content and aging. In this paper, the elements which represent a polarization process are determined from recovery voltage measurement test results by using a new method based on genetic algorithm. The method was successfully tested on a simple circuit and then applied to two power transformers located in hydropower plants. [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]

Chemically prepared graphene was used to form highly active electrodes for use as a cathode in a Li battery. The first discharge process gave a flat discharge plateau at 2.20 V at a current density of 50 mA g−1, and a discharge capacity of 528 mA h g−1was obtained with a cutoff voltage of 2.0 V. [ABSTRACT FROM AUTHOR]

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We developed the world's first middle size full in‐cell LCD for PC with IGZO technology. We evaluated a new Gate driver In Panel (GIP) structure with latch circuit and confirmed that there were no problems with display and touch panel (TP) performance. Furthermore, we did a feasibility study of higher display resolutions and larger size panels, which showed future possibilities. [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]

In flip-chip design, voltage drop reduction in the power ground network has become a challenging problem particularly in the modern Multiple Supply Voltage(MSV) designs. An effective P/G network design and floorplanning- based solutions helps to produce a quality power plan in the layout. Hence, this paper proposes an iterative MSV floorplanning methodology that performs modifications in the existing floorplan representation that satisfies the voltage island constraint and produce an IR drop-aware quality layout. Furthermore, the proposed methodology is integrated with commercial tool design flow to analyze the reduction of IR drop in the layout. Two simulation-based experiments are performed in this paper to showcase the significance of this work. Firstly, it presents the simulation results that benchmark the proposed idealogy in non-flip chip designs. Secondly, the presented framework is integrated in flip-chip layouts of FIR design operating with two voltage islands for low power consumption. To understand the ability of the proposed floorplanning approach, the simulation were performed for two different sized P/G mesh structure for various mesh width. Experimental results from both simulations demonstrate that the proposed MSV floorplanning technique is effective in reducing IR drop while optimizing the design for low power dissipation. [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]

The nonlinear ac–dc composite electric field in the winding area of the converter transformer was studied by considering the frequency and temperature dependence of the insulation materials in this paper. First, the relative permittivity and conductivity of vegetable oils, mineral oils, and insulation papers were measured at different frequencies and temperatures. Then, the oil-paper insulation structure model of one 500 kV converter transformer valve-side winding was established. The nonlinear composite electric field of the converter transformer insulation with vegetable oils and mineral oils was analyzed. The maximum voltage of the converter transformer with mineral oils is 524.9 kV, at −20 °C and that with vegetable oils is 497.1 kV. The results show that the calculation method proposed in this paper is more accurate than the traditional superposition method. [ABSTRACT FROM AUTHOR]

This paper presents an Advanced Excimer Laser Annealing (AELA) process for large-sized OLED displays. Achieving good uniformity and performance characteristics of LTPS TFTs using cost-effective processes are important issues for the production of OLED displays. The AELA uses a conventional ELA system, XeCl laser, large optics and positioning stage, with improved processes and existing technology such as a selective crystallization function. The selective crystallization function of the AELA process has been optimized to obtain uniform microstructure of the crystallized Si films at the TFTs and interconnection region. Specifically, the 7/20 (W/L) TFTs via AELA processed Si films have mobility of 73.81 cm2/V-sec, threshold voltage of −2.07 V and sub-threshold swing of 0.40 V/dec. 55″ FHD OLED displays have been fabricated using the AELA process. The advantages and challenges of AELA technology will be further discussed. [ABSTRACT FROM AUTHOR]

New fluorescence blue host (BH) materials for achieving low voltage have been developed. Low efficiency and short lifetime were main issues to reduce operation voltage when using former generation blue hosts. Therefore new molecular structure of BH was designed to improve both electron and hole mobility and optimize ionization potential (IP) for overcoming the issues. New BHs showed lower voltage and comparable lifetime than former generation BHs. Furthermore, as a result of device optimization using the new BH, low voltage of 3.0V with a high current efficiency of 7.23cd/A, CIE-y of 0.053 at 10mA/cm2 was successfully achieved in a top-emission device. [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]

The basis for judging whether the battery pack is balanced is generally whether the voltage of the battery cell is consistent because the voltage of the battery cell is very easy to obtain. However, when the voltage of battery cells is the same and the battery management system (BMS) turns off the equalization, it will get poor balance performance. In this paper, a new balancing strategy is proposed, while the calculated state of charge (SOC) difference between the battery cells instead of the voltage reaches the set value, the BMS turns on or off, and the difference in the SOC between battery cells is obtained by adding a small amount of calculation to the difference in voltage between battery cells, due to the long balancing time of the battery, the battery will enter a steady state at the end of balancing, based on the voltage difference of battery cell, the voltage drop generated by the balancing current on the ohmic resistance and polarization resistance is added, combined with the open circuit voltage (OCV)‐SOC curve, the difference in battery voltage can be indirectly converted into a difference in SOC. This strategy will appropriately delay the battery balancing time to make up for the drop in the voltage of the balanced battery cell after the BMS turns off the balancing. In this paper, the proposed strategy and performance are analyzed in detail, the experimental platform is designed to verify, and the battery pack is tested under static and discharge conditions. Although the equalization goal is the same voltage between battery cells, using the voltage‐based equalization strategy, the voltage difference between the battery cells is 8 and 6 mV, respectively, while the strategy proposed in this paper is 2 and 3 mV, which has better performance. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental studies about the prebreakdown phenomena in mineral oil under lightning impulse. Experiments were carried out in a non-uniform field setup with HV electrode covered by crepe paper. The results of the experiments were compared with the results of research performed for bare HV electrodes. The onset voltage, propagation velocity, time to initiation, shadowgraph photos of discharges and light emission were respectively measured or recorded during the experiments. Analysis of the research outcomes indicates that the fundamental role of paper insulation is to raise the onset voltage by shoving away the onset sites out of the region of high field stress. The insulation wrapping does not have an influence on the shape of discharge patterns and on the propagation velocity. Some of the results connected with the times to initiation points that the mechanism of discharge initiation at the HV electrode surface does not depend on the fact it is insulated. The source of ?weak points? of the paper-oil insulation system is the oil, not the surface of insulation wrapping or metal of electrode. Observation of the oscillograms of light emitted by discharge channels indicates the difference in the mechanism of discharge propagation. The surface and space charge carriers left in the interelectrode space after discharge flash play an important role. In the case of insulated electrodes, the surface charge remains longer on the surface of electrode, reducing the electric field stress which is responsible for reignition. Simultaneously, the space charge reduces the degree of channel ramification. Both the observations are clearly visible on the oscillograms of light as differences in the frequency of light impulses and their peak values. [ABSTRACT FROM AUTHOR]

The conditions of heat source and heat sink in a geothermal ORC system may frequently vary due to variations in geological conditions, ambient temperature and actual operation. In this study, an off-design performance prediction model for geothermal ORC systems is developed according to special designs of critical components, and an optimal control strategy which regards the turbine guide vane angle, the refrigerant pump rotational speed and the cooling water mass flow rate as control variables is proposed to maximize the net power output. Off-design performances of both subcritical and supercritical ORCs are analyzed. The results indicate that, under the optimal control strategy, the net power output of both ORCs increase with greater geothermal water mass flow rate, higher geothermal water inlet temperature and lower cooling water inlet temperature, which is mainly due to a greater working fluid mass flow rate, higher turbine inlet pressure and lower condensing pressure, respectively. The net power output of supercritical ORC is always greater than that of subcritical ORC within the range of this study, but the difference tends to decrease when supercritical ORC activates the geothermal water reinjection temperature restriction. [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]

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]

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]

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]

A high resolution OLED display was fabricated by using electrohydrodynamic printing method. The printed inks were poly(dibenzothiophene‐S, S‐dioxide‐co‐9,9‐dioctyl‐2,7‐fluorene) (PPF‐SO). Both of the printer operation voltage and the solvent properties dominated the ink's printability and printing stability. Line widths of the printed polymers could be controlled. A mono‐color display with resolution over 2000 PPI was realized. The electrohydrodynamic printing method for fabrication of OLED displays will be discussed in the presentation. [ABSTRACT FROM AUTHOR]

The latest of a series of classified lists of power system relaying references, begun in 1927, is presented. This bibliography is in continuation to the bibliographies of relay literature, which were published previously and are contained in the following volumes of the IEEE Transactions: [ABSTRACT FROM AUTHOR]

This paper presents an online method to monitor the conditions of the substation grounding grid. The proposed method utilizes phase-to-ground faults occurring in downstream feeders as test current sources and the neutral of a specially selected feeder as the electrode for GPR (ground potential rise) measurement. The measured fault currents and GPRs are then used to estimate substation grounding grid impedance. The method, once established, can monitor the grounding grid impedance continuously and automatically, and the trend of the impedance change can be observed. As a result, the proposed method can yield much more reliable information on the substation grounding conditions. The method also overcomes many disadvantages of the offline methods. The proposed idea, algorithm, and hardware setup are described in the paper. Factors contributing to measurement errors are investigated in detail. [ABSTRACT FROM AUTHOR]

A LCD is one of the high power consumption parts in portable devices. Improvement of the power consumption of the display device affects the increase in the duration of a battery in the portable device. One of the most methods to reduce the power consumption is the reduction of the pixel driving voltage. In this paper, we have proposed a novel voltage boost circuit in pixel structures which operates pixels by lower voltage than ordinary pixels. The proposed pixel structure makes the Data voltage up to 400% using by new four capacitors in series. As a result, it reduces the Data and VDD Voltage in a quarter. The CSt3 and Cst4 have been designed approximately three times bigger more than Clc and, we have confirmed that VDD of QoPV becomes 1/3 of VDD of Normal [ABSTRACT FROM AUTHOR]

We devised a threshold voltage compensation pixel circuit using back-gate bias voltage. Variations in threshold voltage can be reduced to 10% while improving the saturation characteristics of a driving transistor. We fabricated a 5.29-in Quad-VGA OLED display using this pixel circuit. [ABSTRACT FROM AUTHOR]

A pure bending semiconductor beam that exhibits a non-homogeneous cross section variation enhanced flexoelectric coupling effect is investigated in this paper from the point of view of theoretical analysis and numerical calculations. According to the macroscopic theory of flexoelectric semiconductors, a one-dimensional bending model for a simple-supported beam with variable cross section is developed. The semi-analytical method, which is composed of cosine series and supplementary functions, is introduced to solve the partial differential equations with variable coefficients. Before the analysis, the convergence and correctness of the semi-analytical method are demonstrated systematically. The calculated results show that both the electric potential and the charge carrier distribute non-homogeneously in the entire beam under a pair of symmetric bending moments. It is revealed that more carriers, a larger electric potential, and more charges tend to concentrate in the zone near the ends. After introducing a dimensionless carrier density, this paper systematically investigates the non-homogeneous cross section variation effect on the flexoelectric coupling for charge carrier redistribution. It is indicated that more perturbation carriers in a non-uniform beam are produced by the enhanced flexoelectric coupling. The demonstration of this concept could be potential guidance for designing new semiconductor devices. [ABSTRACT FROM AUTHOR]

Piezotronic devices have attracted a great deal of attention due to their potential applications in self-powered tactile sensing, nano-device memory, human-electronic interface, etc. As the size of piezotronic devices shrinks, some interesting quantum effects begin to appear. In this paper, we establish a theory oriented to the engineering application of piezoelectric semiconductors, called quantum-corrected phenomenological (QCP) theory, by coupling the density-gradient theory and the linear piezoelectricity theory through Gauss's law. For numerical verification, we specifically studied the electromechanical behaviors in GaN/AlGaN heterostructure quantum wells (QWs) with both infinite and finite barrier height. The results of electron density, electric potential, and quantum potential are provided, and their dependence on the doping density, the applied stress, and the Al mole fraction is investigated. Some interesting quantum effects are revealed, and their influencing mechanisms are well investigated from a macroscopic perspective. Not only do the conclusions drawn in this paper enrich the fundamental understanding of the piezotronic effect in a QW structure, but also the proposed QCP theory can serve as a valuable tool for future device engineering. [ABSTRACT FROM AUTHOR]

The breaking capacity of rated current is one of the important indexes to evaluate the performance of circuit breakers, which is usually measured experimentally and cannot be analyzed in terms of the arcing characteristics of the opening process. Simulation methods based on the magnetohydrodynamic (MHD) model of the arc can be used to obtain the macroscopic motion of the arc within the interrupter and the interaction of the arc with the contacts, walls, and splitter plates. Therefore, this paper focuses on the arc interruption characteristics' underrated current in low voltage circuit breakers by MHD simulation. A more accurate and effective field-circuit coupling MHD simulation model of low voltage circuit breaker products is developed in this paper. A nonlinear conductivity model of the sheath layer is considered to better simulate the near-pole voltage drop and bending processes after the arc has been cut by the splitter. The time-dependent magnetic field generated by the arc is considered in the calculation. Additionally, the real-time parameters of the external circuit are coupled to reflect the evolution of the arc characteristics under the action of the external circuit. The simulation results intuitively and clearly show the evolution of the arc during the breaking process. Through this, an arc extinguishing chamber can be designed to effectively regulate the arc interruption characteristics, thereby improving the breaking capacity of the circuit breaker. The accuracy and efficiency of the proposed simulation method is verified by experiments. This method can be extended to the performance analysis of AC/DC low voltage circuit breakers. [ABSTRACT FROM AUTHOR]

In these paper, we review some nanotube TFET based papers. Based on their device parameters, we decide which device is better for a particular application. Earlier designs gave impressive results, some of them were more focused on subthreshold swing (SSavg) and threshold voltage, whereas some designs are more focused on a good Ion current. We can also see the effect of high-k dielectric which used as gate oxide material for better tunneling current. Drain current (Ion) comparision with several TFET designs are given in this study. As unit parameters, the electric field, electric potential, and energy band diagram have all been observed. [ABSTRACT FROM AUTHOR]

Field electron emission from nanometer-scale objects deviates from the predictions of the classical emission theory as both the electrostatic potential curves within the tunneling region and the image potential deviates from the planar one. This impels the inclusion of additional correction terms in the potential barrier. At the apex of a tip-like rotationally symmetric surface, these terms are proportional to the (single) local emitter curvature. The present paper generalizes this relation, showing that for any emitter geometry, the coefficient of the correction terms is given by the mean curvature, i.e., the average of the two principal curvatures. [ABSTRACT FROM AUTHOR]