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Samples of a dried composite oil-paper system were thermally aged in the laboratory under N2 in a sealed container and analysed using their dielectric response. The contributing loss processes were separated using an equivalent circuit model containing constant high frequency capacitances, dc-conductances, a dispersive capacitance, and a low frequency quasi-dc (q-dc) dispersion process as circuit elements. This low frequency dispersion in oil-paper samples is a bulk property of the system that is often mistaken for a dc conduction process when only the imaginary capacitance or ac-conductance is measured. The Dissado-Hill response function is proposed for the frequency dependence of the dispersive capacitance in the mid-frequency range rather than the Debye function because its cluster concepts correlate with the sample morphology of a matrix of oil-filled cavities. The quasi-dc dispersion is assigned to the transport of mobile charges between charge-clusters associated with locally connected oil filled cavities, which is a process that can be represented on a global scale by the form of hierarchical circuit system that leads to constant phase angle responses, and is here modelled by the Dissado-Hill q-dc function. It was found that the two dispersions moved together to higher frequency with thermal ageing of the composite material. The characteristic frequency common to the dispersions had an activation energy that decreased with thermal ageing, whereas their amplitude increased. This behavior is discussed in terms of possible changes to the oil-paper composite caused by the ageing process. [ABSTRACT FROM AUTHOR]

Frequency domain spectroscopy is a potential tool for non-invasive condition assessment of oil-paper insulation in power equipment. On the other hand, it is well known that the results of frequency domain spectroscopy are affected predominantly by temperature. Moreover, the voltage used for frequency domain spectroscopy is sinusoidal is nature. But the actual insulation system at site is stressed by voltage that may deviate significantly from sinusoid during operation. Considering these two aforesaid facts, in this paper, the response of oil-paper insulation has been studied at different temperatures using both sinusoidal as well as non-sinusoidal excitation. An experimental sample has been prepared in the laboratory that emulates the composite insulation of oil immersed type power transformer at site. The results of frequency response using sinusoidal voltage waveform at different temperature show good agreement with the conventional results that validates the scheme of the experimental setup. Some more information is obtained from the response of non-sinusoidal excitation that could help to get a better interpretation of the actual physical condition of oil-paper composite insulation. [ABSTRACT FROM AUTHOR]

This paper provides an industry perspective on the present state of compact models for MOS transistors. It highlights the complexity of layout-dependent effects in modern transistors, reviews some common misunderstandings of MOS transistor capacitances, and introduces a new, structurally symmetric, “gate-as-input” equivalent network for these capacitances. Areas of focus for the future model developments are also proposed. [ABSTRACT FROM AUTHOR]

Microporous SiO2 can provide large electric-doublelayer (EDL) capacitance and negligible leakage current, owing to lack of electron carrier and limited mobility of mobile ions. The impedance spectroscopy (ionic-conductivity--frequency and capacitance--voltage characteristics) and Fourier-transformed infrared spectroscopy of microporous SiO2 are characterized, which demonstrated that such dielectric is actually a solid-electrolyte dielectric. InGaZnO4 thin-film transistors (TFTs) on paper substrates gated by microporous-SiO2 solid electrolyte are fabricated at roomtemperature.The largeEDL-specific capacitance (1.36 µF/ cm²) results in the paper TFTs operate at a battery-drivable low voltage of 1.0 V. Both depletion-mode (Vth = .0.45 V) and enhancement-mode (Vth = 0.25 V) operations are realized by rationally controlling the oxygen concentration in argon ambient during InGaZnO4 channel deposition. Electrical characteristics with an equivalent field-effect mobility of ~21 cm²/V ⋅ s, a current ON/OFF ratio of greater than 105, and a subthreshold swing of ~80 mV/dec are demonstrated at low frequencies, which are promising for portable paper electronics. [ABSTRACT FROM AUTHOR]

In addition to AC or DC voltages, superconducting electrical equipment must withstand transient overvoltages. Up to a voltage level of 245 kV, equipment has to be tested for its lightning impulse (LI) withstand voltage. Above 245 kV, the test for switching impulse (SI) withstand voltage must also be performed. These transient overvoltages are particularly demanding for compact bifilar coil windings used in resistive superconducting fault current limiters. Therefore the aim of this study is to investigate the LI and SI strength of insulating materials in tape arrangements in liquid nitrogen. Polyimide (PI), a porous insulating paper (Grade 4) and the mixed polymer PPLP (polypropylene laminated paper) in the thickness range of 125 to 130 µm are part of the investigation. The results for LI and SI show the highest values of the dielectric strength for PPLP with 203 kV/mm and 240 kV/mm. PI achieves the second highest values with 194 kV/mm as LI strength and 226 kV/mm as SI strength. With Grade 4, the lowest values are measured at 166 kV/mm and 148 kV/mm, which are, however, surprisingly high for a conventional insulating paper. Additionally, Grade 4 is the only material with a higher LI strength than SI strength. Compared to the AC strengths, the values of the impulse strengths are higher for all materials investigated, with the exception of PI, where the AC strength is in the same range as the SI strength. [ABSTRACT FROM AUTHOR]

The first part of this paper presented mymargin the device-level comparison of emerging materials (In0.53Ga0.47As and 2-D materials) and device architecture (NW FETs) with s-Si FinFETs. In order to further understand the performance and energy efficiency of these device options for future technology nodes, it is required to go beyond the device-level comparison by accounting for not only intrinsic but also the extrinsic parasitic elements. In this paper, we present the comparison of s-Si, In0.53Ga0.47As, and 2-D material-based n-type MOSFETs using the circuit-level figure of merits across three successive future technology nodes. The analysis incorporates both device characteristics obtained from an advanced quantum mechanical simulation tool and circuit-level comparison, which accounts for device parasitic elements and wiring load. The results show that 2-D material DG MOSFETs present a more energy-efficient device option than s-Si and In0.53Ga0.47As FinFETs in sub-0.7-V supply voltage regime and In0.53Ga0.47As nanowire (NW) FETs can outperform s-Si multi-gate (MuG) FETs and 2-D material FETs, but when considering non-idealities, s-Si NW FETs remain both faster and more energy-efficient device option. [ABSTRACT FROM AUTHOR]

The Potential Transformer (PT) plays an important role in the measurement and monitoring of the power system. The accurate modeling of the PT is very important but not yet perfect. The stray capacitance will have a non-negligible effect on the performance of a PT. However, the influence of stray capacitance is rarely considered in existing models, which makes the broadband simulation performance weak and provides limited references in engineering. In this paper, a calculation method of PT stray capacitance is proposed to analyze the performance of the PT at different frequencies and extract the capacitive current of the PT port. This paper used a non-destructive method to obtain the test data of a PT, calculated the value of the stray capacitance, and drew the hysteresis loops of the iron core. A corresponding simulation model was established to predict the PT performance at different frequencies. The simulation results are in good agreement with the experimental data, which proves the accuracy of the modeling parameters. The data processing logic is clear and is easy to be simplified by programming, which makes it promising in engineering. [ABSTRACT FROM AUTHOR]

Frequency Domain Spectroscopy (FDS) is mainly used to determine the moisture in the paper-oil insulation systems in power transformers and Oil-Impregnated-Paper (OIP) bushings. Another application of this method is detection of puncture developing in the paper layer between the adjacent conductive foils in the condenser core. The paper presents theoretical calculations of tan? frequency response in the case of short circuit of conductive layers in bushing's condenser core and their experimental verification, with the help of paper-oil insulation capacitor. Furthermore, examples of measurements of real bushings in operation that agree with the proposed idea are described. [ABSTRACT FROM AUTHOR]

Insulators or bushings are one of the most common cause of transformer failures especially those with fire and collateral damage. This can be prevented by application of off-line and on-line monitoring, especially by measuring of capacitance C and dielectric dissipation factor tanδ, but current physical understanding of these parameters should be improved. A complex research of temperature dependence of C and tanδ, which is based on measurements on a specially designed oil impregnated paper bushing models with different moisture contents in the insulation and during artificial ageing, is presented in the paper. Useful relationships, which enable calculation of tanδ as a function of observed influencing parameters, are also presented. [ABSTRACT FROM AUTHOR]

In this paper, an inner ultrathin oxide metal–oxide–semiconductor (MOS) capacitor is fabricated with another outer MOS-gate ring as a coupling controller. Capacitance–voltage characteristics of inner MOS capacitor show that the excess minority carriers supplied from the outer MOS-gate ring can efficiently change the inner capacitance (${C} _{\text {inner}}$). It is observed that outer MOS-gate ring under the conditions at floating and at ground has quite different coupling effects on ${C} _{\text {inner}}$ when the inner MOS is biased at 1 V. Comparing to ${V} _{\text {outer}} = \text {floating}$ , ${C} _{\text {inner}}$ reduces significantly when ${V} _{\text {outer}} = {0}$ V at 1k Hz. The transient behavior of ${C} _{\text {inner}}$ as ${V} _{\text {outer}}$ changes from 0 V to floating is long enough to read, and the difference of two capacitance values can be regarded as two states. As a result, a two capacitance states operation is proposed for possible memory application. Based on the experimental results, the possible memory cell configuration is designed. Comparing to the present emerging memories, since the two states in this paper are in conditions of floating and 0 V, ultralow power is consumed, which is believed a promising concept for future memory application. [ABSTRACT FROM AUTHOR]

In this paper, a novel technique to improve the fault detection sensitivity in a three-phase transformer using the tank current method is reported. The tank current method was first published by the first author in recent past for single isolated transformer winding. A fault in single isolated transformer winding was uniquely identified employing the typical resonance behavior of tank current, but for three-phase transformer, such implementation is yet to be explored. The present scope of this paper is only for uniformly wound three-phase transformer windings. Implementing the tank current method for such a three-phase transformer may not be very simple, since the neighboring windings, unlike in the case of isolated winding, strongly influence the measurement of the tank current. Therefore, this paper appropriately considers the effect of neighboring windings in a three-phase transformer and investigates the resonance behavior of its tank current to propose a promising innovative extension approach of the method. Experimental results on actual transformers are also presented for practical validation of the proposed method. Results imply that the tank current method is indeed very sensitive to identify the fault in an actual transformer compared to the conventional neutral current method. The authors also believe that the method needs to be reinforced by field measurements on several transformers to ascertain its viability. [ABSTRACT FROM AUTHOR]

Ground wires (GW) struck by lightning are often exposed to transient impulse voltages in the MV range. This results in intense negative streamer-type corona, causing a considerable increase in the effective wire capacitance and a corresponding reduction in its surge impedance. Such variables have a significant influence on the tower top potential and on the electromagnetic coupling between the ground wire and phase conductors. Presently there is considerable uncertainty regarding the impulse corona parameters to be used in back flashover calculations. In the present paper a new method is formulated for determination of GW impulse corona parameters. The new approach is compared with two existing methods and with available experimental results. It is found that the method usually used within the IEEE has little physical justification and is excessively conservative. It is also shown that such corona parameters significantly depend on the GW height above ground, which has been totally ignored in the CIGRE method. This and other unjustified simplifying assumptions explain the surprisingly large discrepancy between values of the negative impulse corona constant recommended by CIGRE and IEC. [ABSTRACT FROM AUTHOR]

While much attention was given in the literature to improve the fault ride through (FRT) capability of a doubly-fed induction generator (DFIG)-based wind energy conversion system (WECS) during various faults at the grid side, not much attention was given to investigate and improve the performance of the DFIG-WECS under ferroresonance conditions. This paper investigates the impact of ferroresonance on the overall performance of a DFIG-WECS. The paper also presents a new technique to improve the high voltage ride through capability of the investigated system under such condition. The proposed technique relies on incorporating a superconducting coil within the dc-link of the DFIG grid-side and rotor-side converters. Energy exchange between the coil and the system is controlled through regulating the duty cycle of the dc-chopper interfacing the coil with the dc-link. In this regard, a simple but yet effective proportional-integral (PI) controller is employed to regulate the dc-chopper duty cycle. Parameters of the PI controller are optimized using elephant herding optimization algorithm. Simulation results verify the effectiveness of the proposed controller in improving the overall performance of a DFIG-WECS during ferroresonance events. [ABSTRACT FROM AUTHOR]

Vertical interconnects used in monolithic 3-D integrated circuits (3-D ICs), so-called monolithic interlayer vias (MIVs), are as small as local vias. Thus, redesigning an existing 2-D IC layout in a monolithic 3-D IC generally results in shorter wire length than the 2-D IC layout. In addition, MIVs have almost negligible resistance and capacitance, so their impact on signal delay is very small. Thus, redesigning a 2-D IC layout in a monolithic 3-D IC is expected to improve its performance significantly. Some researchers designed several monolithic 3-D IC layouts and showed their timing benefits in the literature. In this paper, we present analytical models for performance (timing) benefits of multitier gate-level monolithic 3-D ICs. The analytical models we develop in this paper can be used to quickly estimate the performance benefits multitier gate-level monolithic 3-D integration provides without physically redesigning 2-D IC layouts in 3-D. [ABSTRACT FROM AUTHOR]

In negative capacitance field-effect transistors (NCFETs), drain current may decrease with increasing ${V}_{\mathrm {ds}}$ in the saturation region, leading to negative differential resistance (NDR). While NDR is useful for oscillator design, it is undesirable for most analog circuits. On the other hand, the tendency toward NDR may be used to reduce the normally positive output conductance ( ${g}_{ \mathrm {ds}}$ ) of a short-channel transistor to a nearly zero positive value to achieve higher voltage gain. In this paper, we analyze the NDR effect for NCFET in the static limit and demonstrate that it can be engineered to reduce ${g}_{\mathrm {ds}}$ degradation in short-channel devices. Small and positive $g_{\mathrm{ ds}}$ is achieved without compromising the subthreshold gain, which is crucial for analog applications. The 7-nm ITRS 2.0 FinFET with 0.7 V ${V}_{\mathrm {dd}}$ is used as the baseline device in this paper. [ABSTRACT FROM AUTHOR]

This paper proposes a robust to defects and short length device (RDSLD), a newly in-plane resonant tunneling diode (RTD), and its ac-modeling with the minimum length of 3 nm. The proposed structure has robust performance in the presence of defects. It also has a high degree of flexibility in tuning electronic specifications. By using bipolar doping and a special h-boron nitride barrier pattern, these unique features are obtained. The simulation results verify that the proposed structure has the potential for replacing conventional RTD diodes. Such that the peak-to-valley ratio (PVR) and the maximum current of 4500, 450 nA for perfect bowtie and 3.45, 1256 nA for rhombic barrier shape structure are obtained, respectively. Also, negative differential resistance (NDR) is observed in all of the structures with vacancy and impurity defects. The effect of the geometrical parameters on the charge transmission of the device is another issue that is addressed in this paper. Furthermore, the analytical and numerical capacitance model parameters are presented. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel reconfigurable ferroelectric FET (R-FEFET), which can reconfigure its operation between volatile and nonvolatile modes during run-time by dynamically modulating its hysteresis. The R-FEFET comprises of two gates with ferroelectric (FE) in both the gate stacks. One of these terminals serves as a regular gate, while the other is used as a control to introduce reconfigurability. Employing Landau–Khalatnikov equation-based FEFET model, we extensively analyze the device characteristics in both FinFET and planar technologies. We show that by changing the control voltage between 0 and 1 V, the hysteresis width (HW) can be modulated between 1.1 and 0.3 V. In addition, we show the device characteristics and advantages that R-FEFETs possess to overcome the drawbacks encountered with gate leakage in standard FEFETs. The hold margins in the nonvolatile mode of R-FEFETs increase by ~ $10\times $ with respect to standard FEFETs, and the drive current strengths in the volatile mode show 13% improvements when compared to standard FETs. Using the proposed R-FEFETs, we examine a low-power nonvolatile memory design in Part II of this paper. [ABSTRACT FROM AUTHOR]

This article investigates energy storage requirements in the submodules of a class of converters known as hybrid cascaded modular multilvel converters (HC-MMCs). The complexities arising from the usage of different submodule types and their non-conventional arrangement necessitate detailed analysis of submodule capacitor voltage ripples, which are needed for development of guidelines for sizing submodule capacitors. This paper characterizes electric charge variations in the submodule capacitors to derive expressions for capacitor voltage ripples, and to determine the energy storage requirements of the converter. The paper uses detailed electromagnetic transient (EMT) simulations and experimental results on a laboratory-scale MMC setup to verify and validate its findings. [ABSTRACT FROM AUTHOR]

Increased drain-induced barrier lowering caused by drain electric flux (or field) passing through the buried-oxide (BOX) layer in silicon-on-insulator (SoI) MOSFETs has been reported as an inherent disadvantage of SoI technology. Part I of this paper discussed derivation of the relationships between coordinates in MOSFETs and potential/stream function in preparation for the modeling of electric flux using conformal mapping in subthreshold regions of ground plane SoI MOSFETs and the validity of the approach was checked via device simulation. Here, in Part II of this paper, we discussed the model’s derivation based on these relationships. The dependences of the flux amount on BOX thickness, BOX permittivity, SoI thickness, and gate length estimated using the model were also discussed in comparison with those estimated via device simulation. [ABSTRACT FROM PUBLISHER]

With the increasing of switching frequency in pulsewidth modulated motor system, common mode current (CMC) seriously affects the reliable operation of motor system and it has become a problem that cannot be ignored. This paper proposes a mathematical model of CMC and conducts detailed time–frequency characteristics analysis of CMC. The influence of several key parameters of motor system, such as distributed capacitance, dc bus voltage, and inverter switching frequency, on CMC characteristics has been analyzed in detail, and the corresponding variation rule of CMC oscillation amplitude and attenuation period/time has been summarized. The experimental results are presented to verify the correctness of theoretical analysis. The conclusions of this paper can lay theoretical foundation for the effective suppression of CMC in various practical applications. [ABSTRACT FROM AUTHOR]

External electrode fluorescent lamps (EEFLs) are used as backlight source for large screen size liquid-crystal displays. Since electrodes are outside of the discharge tube, lifetime is enhanced when compared with cold cathode fluorescent lamps. Also, a single inverter can drive multiple EEFL tubes, leading to a compact design, driven by sinusoidal or square waveforms. Luminance can be enhanced by synchronizing the moment of the self-discharge of the dielectric wall charge with voltage rising and falling. This paper presents luminance measurements for different driving alternatives and lamp voltages, showing that EEFLs have an electrical behavior similar to dielectric barrier discharge lamps and light emission similar to the conventional fluorescent lamps. It is also shown that sinusoidal operation is more efficient than square wave operation in the light emission sense for the explored conditions. [ABSTRACT FROM AUTHOR]

The application of stacked-FETs in power amplifiers allows for a supply voltage higher than supported by the breakdown voltage of a single transistor. Potential benefits of the increased supply voltage are reduced supply currents and a lower matching ratio at the output of the amplifier. Furthermore, an increased output power per chip area is obtained due to the reduction in passive structures resulting in more area-efficient power combining. In this paper, the procedure for the design of integrated microwave stacked-FET is discussed. Several options for the correct distribution of RF voltage and current swings are investigated and the relationship between the number of stacked transistors and bandwidth is addressed. The procedure is demonstrated by the design of an S-band GaAs stacked-FET containing three transistors. This stacked-FET is applied in an S-band HPA that has a PAE of more than 40% at an output power of 20 W, which is more than twice the output power of any previously reported GaAs stacked-FET HPA. [ABSTRACT FROM AUTHOR]

This paper presents a unique methodology to calculate the filtering capacitances of the OpAmp already reported in the literature. The methodology aims to show that there is an optimal solution that can be used to increase the electromagnetic interference (EMI) immunity of any OpAmp for a wide range of frequencies. By using this proposed methodology, an OpAmp structure that reduces the EMI effect is designed in standard 0.18\ \mu \textm mixed-mode CMOS technology. Detailed mathematical analyses and simulation results are presented and discussed. Simulation results show that the maximum EMI-induced offset voltage in the frequency range from 1 MHz to 1 GHz for the OpAmp is 4.4 mV. In contrast, the standard Miller OpAmp exhibits a maximum EMI-induced offset voltage of 92.4 mV under the same operating conditions. [ABSTRACT FROM PUBLISHER]

For Rogowski coil, as the current carrier passes through the coil center, it fails to locate the lightning current. With the aim of measuring and locating the lightning current at the same time, this paper developed a lightning current sensor. In this paper, the physical model, geometric parameters, and manufacturing process of the lightning current sensor were introduced, and then a novel sensor coil was developed. To verify the reliability of the sensor, experiments were also performed. The good response characteristics of the sensor were also demonstrated. Last but not least, the sensitivity of the sensor was calibrated, and the formula was determined, which demonstrated sensor output voltage and derived by current and distance, providing theoretical and experimental evidence for practical application. [ABSTRACT FROM AUTHOR]

A novel high-voltage direct current (HVdc) power supply which has no transformer or voltage multiplier circuit is presented and analyzed in this paper. This is made possible upon the diodes storage delay phenomenon. This proposed power supply is compact, lightweight, and low cost. Its basic structure includes a diode with a proper reverse recovery specification that plays the role of a step-up transformer in the conventional HVdc supplies and a high-voltage capacitor which stabilizes the output voltage. This structure has remarkable advantages over the conventional transformer-based HVdc supplies, such as compactness, a low ripple output, and a low-cost power supply. Performance of the proposed method and its accuracy are investigated in this paper. The results are verified by implementation of a 1.2-kV prototype supply. [ABSTRACT FROM AUTHOR]

Melamine formaldehyde microspheres are widely used in dusty plasma experiments for their monodispersity, sphericity, low mass density, and well defined sizes. This paper summarizes problems that were encountered in numerous applications of these grains in different laboratory simulations. and the already published results are discussed in view of new experiments. The main results of this paper are connected with changes of the grain mass due to the decreased pressure and/or increased temperature and variations of the grain dimensions, its shape, and mass density under electron or ion bombardments. By contrast to the work function estimated from field emission properties, we have found the photoelectric work function (4.5 eV) being close to that expected. A sputtering of the grains using a 30-keV ion beam revealed their unexpected heterogeneity. [ABSTRACT FROM AUTHOR]

In this paper, a physics-based compact model for calculating the semiconductor charges and gate capacitance of III-V nanowire (NW) MOS transistors is presented. The model calculates the subband energies and the semiconductor charges by considering the wave function penetration into the gate insulator, effective mass discontinuity at the semiconductor-oxide interface, 2-D confinement in the NW, and Fermi-Dirac statistics. The semiconductor charge expression proposed in this paper is completely explicit in terms of applied gate voltage, therefore, making it highly suitable for large circuit simulations. The model is also compared with the results from self-consistent Schrödinger-Poisson solver for different NW sizes and materials and found to be accurate over a wide range of gate voltages. [ABSTRACT FROM AUTHOR]

With lots of interest in negative capacitance field-effect transistors for ultralow-power complementary metal-oxide-semiconductor technology, negative capacitance thin-film transistors (NCTFTs) have also received much attention. Although previous studies on NCTFTs were done, the NC effect in organic-based TFTs was not studied yet. In this paper, P(VDF-TrFE) ferroelectric-gated P3HT semiconductor channel TFTs are experimentally demonstrated with solution-based fabrication process. Especially, this paper shed light on the NC effect in the organic based TFTs. The step-up current-voltage characteristics are repeatedly and reliably observed in diverse TFTs, and then, with the results, transconductance (gm) amplification implemented by the negative capacitance was delved. Moreover, with the aid of ferroelectric polarization switching, super steep-switching characteristic of the organic-based TFT was experimentally confirmed. These experimental results and discussion would be helpful in understanding NC effects in TFTs. [ABSTRACT FROM AUTHOR]

This paper presents the effect of stray capacitances in bipolar (negative and/or positive) pulses generated by the two different topologies of the solid-state Marx modulators. According to the analysis, the stray capacitances influence the energy transfer from the Marx modulator capacitors to the load affecting the bipolar (negative and/or positive) pulse rise time. This paper deals with the structure design to reduce the influence of the stray capacitance and to improve the pulse rise time of these bipolar solid-state Marx modulators. A four-stage laboratory prototype of the two topologies has been assembled using 1200-V insulated gate bipolar transistors and diodes, operating with 1000-V dc input voltage and 1-kHz frequency, producing 4-kV bipolar pulses, with 5- \mu \texts pulse duration and 120-ns rise time, into a resistive load. [ABSTRACT FROM PUBLISHER]

When a single-phase-to-ground (SPG) fault occurs in distribution networks, the existing faulty feeder detection techniques do not present reliable detection results. This paper introduces a novel faulty feeder detection method based on transient energy and cosine similarity. First, the fault characteristics of transient zero-sequence current (TZSC) are analyzed. It is found that the fault transient characteristics of transient components decrease as the grounding resistance increases. Second, to fully maintain the fault transient features, a fundamental frequency component (FFC) shifting method is introduced to remove FFCs. Next, the transient currents without containing FFCs are utilized to generate two fault indicators: transient energy within the first half power cycle and cosine similarity after the first half power cycle. After that step, to effectively merge the two fault indicators, the Laplace distribution is utilized. The fault possibility of each feeder can be quantitatively estimated by calculating the cumulative density function (CDF). Finally, the feeder with the maximum fault possibility is determined as the faulty feeder. The effectiveness and applicability of the proposed detection method are verified in the radial distribution network and the modified IEEE 34-bus distribution network. The results of the field test also indicate the feasibility of the proposed SPG detection method. [ABSTRACT FROM AUTHOR]

Recent advances in the fabrication technology have yielded nanometer-scale InGaAs quantum-well (QW) MOSFETs with extremely low and reproducible external contact and access region resistances. This allows, for the first time, a detailed analysis of the role of ballistic transport in the operation of these devices. This paper presents a systematic analysis of external resistance, ballistic resistance, and channel mobility in InGaAs QW-MOSFETs under near-equilibrium conditions, i.e., under very low drain-source bias. This is an important regime for device characterization. Devices with a wide range of channel lengths, from 70 to 650 nm, are investigated. Our analysis includes the consideration of the impact of carrier degeneracy in the QW channel. We show that unless the ballistic behavior in the intrinsic channel is accounted for, the standard extraction technique for external resistance grossly exaggerates its value as it incorporates the so-called ballistic resistance. By separating out the ballistic resistance, the external resistance in our devices is shown to be extremely low, $74~\Omega $ - \mu \text{m} , including both source and drain sides. This is thanks to our contact-first self-aligned Mo-contact technology. Furthermore, taking the advantage of the wide range of ballisticity of the devices studied in this paper, we demonstrate a methodology to self-consistently extract scattering-dependent effective mobility, mean-free-path length, and ballistic mobility. [ABSTRACT FROM AUTHOR]

This paper presents a numerical method for calculating the resistance, inductance, and capacitance matrices of transformer windings. Importance of their precise calculation is shown in the simulation of voltage distribution over the windings for a lightning-impulse test. The results obtained in frequency domain analysis are in good agreement with the measurement data. All the parameters are calculated using the self-developed solvers, the theory and the novelty of which are described in this paper. The presented approach allows fast and accurate high-frequency modeling of transformer windings. [ABSTRACT FROM AUTHOR]

In analog designs, the most widely adopted layout practice to improve matching is the symmetrical common-centroid placement. However, this arrangement cannot be obtained in general. In this paper, it is shown that there are asymmetrical placements with a common centroid which are also immune to process gradients and suitable for designs where a symmetrical layout is not possible. In addition, this paper proposes an automated method, based on a standard simulated annealing framework, to arrange fully-integrated capacitors in a layout to improve their matching. [ABSTRACT FROM PUBLISHER]

Risk of arcing in space plasma environment on satellite solar panel has always been an issue of major concern in the aerospace community. The outcome of round robin tests performed in various laboratories has resulted in finalization of the guidelines for the ground test of satellite solar panel coupons (SSPCs). This is documented as ISO-11221 standards. Authenticity of arc plasma flashover (FO) parameters are still under debate. Some experimental findings that support the perimeter theory of arc FO on geostationary (GEO) satellites are discussed in this paper. It has been observed that characteristics of an the arc are dependent on its location on the solar coupon, bias charge (charge due to bias voltage and external capacitance), and the total charge dissipated during the arc discharge. It is also observed that the duration between the two consecutive arcs is directly proportional to the dissipated charge or energy of the latter arc. A combined dielectric consisting of solar cell, adhesive, Kapton, and Carbon Fiber Reinforced Polymer sheet holds charge during irradiation by the electron gun. This resembles surface FO capacitance. Arc energy is governed by the combined effects of a surface flashover capacitor (C-sf) and an external capacitor. It is observed that if intermittent arc duration is sufficiently longer than the gradual accumulation of charge on the SSPC, body may lead to a major arc. This would increase the probability of secondary arcs when the sustained arc environment is experienced by the satellite. To understand primary arcs on dielectrics, an artificial triple junction is prepared and exposed under adverse GEO-like space conditions. Various signatures identified from the arc current and arc neutralization current waveforms specify the behavior of these arcs at different locations on the coupon surface. In this paper, current waveforms of arcs captured on different types of solar panel coupons and their significance are studied. Information about arc energy, arc velocity, and neutralization velocity are extracted from the measured waveforms. [ABSTRACT FROM PUBLISHER]

Energy harvesting has attracted increased attention recently. Energy sources are present all around us, such as, mechanical vibrations, stress, strain, waste heat, sunlight or room light, electromagnetic rays, and chemical or biological sources. Vibration generators based on piezoelectric elements have been highlighted as low-power sources; however, their output power is very low, around the milliwatt or microwatt level, and thus, improving their performance is necessary to make the generated power usable. This paper investigates the use of passive devices to improve output characteristics of the vibration generators. The proposed circuits are a resonator and a passive rectifier. The proposed resonator consists of a parallel inductor and capacitor for $LC$ resonance. The $LC$ resonance equivalently reduces the internal capacitor of the piezoelectric elements. As a result, the output voltage and power are increased compared with that of conventional circuits. In addition, a boost-type current-improving passive rectifier is applied as the passive rectifier. The validity of the proposed circuit is numerically and experimentally verified. [ABSTRACT FROM AUTHOR]

The ultimate objective for transformer winding fault diagnosis is fault location and even severity evaluation. The issue has been studied in many works, based on frequency response analysis, using numerical indices or mathematical correlation between ladder network and winding. This paper utilizes Gauss–Newton iteration algorithm (GNIA) to diagnose winding faults for its efficient search of optimal parameters and discrimination of linearly-dependent vectors. Three key problems are handled for the application of GNIA in this paper. The first problem is the establishment of connection between ladder network components and frequency response function in GNIA. Another issue is the method to identify the faulty section to locate the defective winding position. The assessment of fault severity with GNIA data is another challenge. GNIA is applied on an air-cored model coil and a customized transformer successfully, with satisfactory diagnosis on deformation location and severity. [ABSTRACT FROM AUTHOR]

In this paper, we report the characterization and modeling of multi-finger gate all around (GAA) nanowire (NW) FETs (NWFETs) from dc to 14 GHz. The self-heating effect (SHE) in NWFETs is investigated experimentally using the small-signal output conductance (${g}_{{\text {ds}}}$) technique. The frequency-dependent complex thermal impedance, ${Z}_{{\text {th}}}({f})$ , is extracted by fitting an ${n}$ th-order thermal network with the experimental data. We show that the temperature rise $\Delta {T}$ (=85 °C) due to SHE is significant in short-channel silicon on insulator (SOI) NWFETs. Finally, we have evaluated the RF figure of merit (FOM) for these NWFETs as ${f}_{T}$ (=70 GHz) and ${f}_{\text {max}}$ (=80 GHz). We also report the RF performance metric sensitivity on temperature, $\partial {f}_{\text {max}}/\partial {T}_{{\text {amb}}}$ ($\approx -0.104$ GHz/K). The reported BSIM-CMG compact model shows a good correlation with the measurement data. [ABSTRACT FROM AUTHOR]

In this paper, AlGaN/GaN high-electron mobility transistors (HEMTs) with different fin configurations are fabricated and analyzed. Through S-parameter measurements and modeling of the designed devices, a detailed RF investigation on small-signal model parameters is performed under different biasing conditions. Good agreements between measured and simulated scattering parameters up to 40 GHz illustrate the validity and accuracy of the model. The influence of different fin structures on model parameters and linearity improvement is examined, and this can help to improve the frequency characteristics of fin structure by optimizing the fin length, fin width, and trench width. The significant linearity of Fin-HEMTs is confirmed by the analysis of the model parameters, which is the first time to study the small-signal characteristic of AlGaN/GaN Fin-HEMTs in detail. [ABSTRACT FROM AUTHOR]

In this paper, we argue that communication at the speed of light (CaSoL) through on-chip copper interconnects is possible in the near future based on giga-scale integration (GSI) technologies. A three-step algorithm is introduced to design the optimum buffers in such systems. HSPICE simulations show that a $1.3\times $ time of flight (${T}_{\text {F}}$) is reachable in 7-nm FinFET technology. It is also shown that such a design is by nature, robust, and immune to process variations and crosstalk noise. [ABSTRACT FROM AUTHOR]

This paper investigates the advantages and disadvantages of bonding pad over active area (BPOA) layout over a conventional layout for lateral AlGaN/GaN HEMTs designed for use in power applications. Extensive analysis of the performance of a BPOA device, both experimentally and supported by 3-D TCAD model simulations, reveals that while it can offer a higher current capability per unit area, it can lead to other disadvantages compared to a conventional design when considering reliability aspects. [ABSTRACT FROM AUTHOR]

In this paper, a modular topology is presented for generating high-voltage pulsed power. The proposed structure consists of Marx-type modules, which are based on the switched-capacitor (SC) concept. This module receives an input voltage and, depending on the requirement of the user, produces an output voltage either equal to the input or twice as much as the input voltage, which shows the flexibility of our model. The capability of the module to produce a doubled output makes it appropriate for applications with low input voltage sources. Also, the topology has the capability of generating combined wide and narrow pulses. The topology was simulated in MATLAB Simulink and a laboratory setup was built to test its operation. The results validate the theoretical basis of the structure. [ABSTRACT FROM AUTHOR]

This paper presents a differential-input, differen tial-output charge amplifier topology built with discrete, commercial components. The amplifier is designed to interface high-impedance ultrasonic sensors made of piezoelectric polymer, with a required bandpass of at least 100 kHz to 1 MHz, and needs to operate from a single 5-V supply. The performance and tradeoffs of the proposed topology are evaluated analytically and using a circuit simulator, showing a charge-to-voltage conversion gain in excess of 240 dB[V/C], while maintaining an input impedance lower than 100 $\Omega$. Simulations and measurements of a prototype implementation are presented. [ABSTRACT FROM AUTHOR]

In this paper, a comparison of gate-all-around nanowire-FETs, nanoplate (NP)-FETs, and FinFETs was undertaken for the same areas of not only the gate metal but also the silicon channel, assuming the same conditions regarding the parasitic components. It is known that an NP-FET structure not only improves the delay performance but also enhances the immunity to short-channel effects. In addition, it is found that the use of a dual-k spacer with an NP-FET further improves the on-state as well as the off-state performances. [ABSTRACT FROM AUTHOR]

In this paper, we propose a physics-based compact model of the pinned photodiode (PPD) combined with the transfer gate. A set of analytical expressions is derived for the 2-D electrostatic profile, the PPD capacitance, and the charge transfer current. The proposed model relies on the thermionic emission current mechanism, the barrier modulation, and the full-depletion approximation to obtain the charge transfer current. The proposed physics-based model is fully validated with technology computer-aided design simulations, i.e., stationary and optoelectrical simulations. The development of such a compact model for PPD represents an essential step toward the design, simulation, and optimization of PPD-based pixels in CMOS image sensors. [ABSTRACT FROM AUTHOR]

Photoelectric characteristics are an important reference for high-voltage discharges and are closely related to the excited mode of the high-voltage source. In this paper, we built a large-scale volume dielectric barrier discharge (DBD) system, which is composed of multilayer parallel-plate DBD electrodes and is excited by a high-voltage source in the power density modulation (PDM) mode. Subsequently, we analyzed the applied energy equation and evaluated the DBD systems photoelectric characteristics. The results show that the energy values of different applied voltage cycles during a PDM period exhibit significant differences. However, the average energy in a PDM period is approximately constant. Moreover, the equivalent capacitance of the DBD cell is a function of both the applied voltage and energy density. For the DBD cell, with the increase in both the applied voltage and energy loaded on the DBD cell, the total equivalent capacitance ($C$) is approximately constant, the dielectric capacitance ($C_{\mathrm{ d}}$) increases exponentially and decreases linearly, while the discharge gap capacitance ($C_{\mathrm{ g}}$) decreases and increases in the same cases. In addition, the relative intensities of the discharge emission increase and the energy efficiency ratios of the relative photoquantum yield of active species decline with the increase in both the applied voltage and energy density loaded on the DBD cell. The experimental results have been analyzed by evaluating the influence of the electrical parameters, and the underlying physical principles have been discussed. This paper clearly demonstrates that the photoelectric characteristics of the DBD reactor are significantly influenced by both the applied voltage and energy density, thus providing helpful insights into the energy evaluation and application of high-voltage discharges. [ABSTRACT FROM AUTHOR]

Nonlinear transmission lines (NLTLs) have been studied over the past several years to generate high-power radio frequency signals. Their operation consists of a lumped line based on the nonlinear behavior of the LC section components, capacitors or inductors, as a function of the applied voltage or current, respectively. However, considering high-power signals, the application of these devices using nonlinear ceramic capacitors as the capacitive lumped lines are restricted to frequencies around 100 MHz since at high voltages, parasitic impedances in the line structure limit the maximum operating frequency. On the other hand, the use of variable capacitance diodes has enabled the operation of NLTLs at higher frequencies. This paper provides the results of a study of NLTLs for RF generation based on silicon carbide Schottky diodes. The principle of operation and its simplified theory are presented. Initially, the voltage dependence of the diode capacitance is modeled. Experimental and simulation results are compared. Frequency oscillations around 200 MHz were generated. The extraction of the radio frequency energy is realized, and the radiation of the electromagnetic wave is performed using double-ridged horn antennas. Finally, some parameters are analyzed, and all results discussed. [ABSTRACT FROM AUTHOR]