Voltage Divider Research Articles

Bismuth sulfide based resistive switching device as the key to advanced logic gate fabrication

A memristor is a two-terminal electrical component with the scope of future computing applications and analog electronics. In this report, bismuth sulfide decorated one-dimensional carbon nitride nanotube was synthesized and characterized with various analytical techniques. The electrical property of the synthesized material was measured using a two-terminal metal–insulator–metal type of device that exhibited the resistive switching characteristics with the ON to OFF ratio of 2 × 103. The electron transport mechanism of the device was followed by Schottky emission and Poole–Frenkel emission for a low conductance state and Ohmic conduction behavior at the high conductance state. A decrease in the trap depth was identified in the simulation study with increasing applied potential and that supported the proposed mechanism. Read endurance and retention behavior of the device are stable in nature, supported by the statistical analysis. Furthermore, a hybrid logic gate was designed using two identical memristors, one CMOS inverter, one resistor, one voltage divider, and a buffer gate. The designed logic gate exhibited stable nand and nor gate operation based on the control signal.

A Five-Level Transformer-Less Grid-Tied Inverter Structure With Capacitive Voltage Divider Concept With Leakage Current Elimination

This paper presents a novel single-phase inverter with six switches and five levels that shares a common ground and does not require a transformer. The proposed inverter is intended for use in photovoltaic systems that are connected to the grid. The proposed inverter is derived from the concept of a capacitive voltage divider (CVD) circuit, so that, the leakage current will be eliminated. The CVD circuit produces three levels of output voltages in the proposed inverter. The proposed novel inverter has several significant advantages, such as the elimination of leakage current without the need for additional components, the ability to transfer reactive power fully, and the use of fewer components compared to current five-level transformer-less inverters. Additionally, the voltage stress is evenly distributed across power switches, resulting in higher efficiency. Furthermore, the inverter is designed to automatically balance voltage in capacitors without requiring an additional control system. The proposed inverter achieves these advantages using a suitable switching scheme. The paper also includes an explanation of the proposed circuit, the process for designing minimum capacitors, theoretical loss calculation, and a comparison of features with similar topologies todemonstrate the efficiency of the proposedinverter. Inaddition, a 1 kVA experimental prototype is constructed to showcase the effectiveness of the proposed inverter.

Calibration Method of a Wideband AC Resistance Voltage Divider Based on an Equivalent Model.

Aiming at the problem of large measurement error and phase shift in resistance voltage dividers under high-frequency conditions in the field of power measurement, such as power harmonics, an error correction method is proposed for an alternating current (AC) resistance voltage divider based on the equivalence principle. Firstly, the frequency error model of the AC resistance voltage divider precision is established, and the angle difference of the continuous spectrum ratio difference from 50 Hz to 100 kHz is corrected by determining the shielding structure and the resistance parameters and fine-tuning the shielding potential correction method to reduce the capacities error of the AC resistance voltage divider design precision. At the same time, the performance parameters such as the direction and magnitude of the shielding potential compensation capacitive error are investigated. Finally, the precision voltage divider (the maximum voltage applied is 480 V) calibration experiments verify that the important characteristic judgment factor of the voltage divider is independent of the frequency and the equivalent capacitance value, which effectively solves the phase correction problem of harmonic power measurement.

Virtual design of a measuring device integrated in electroacupuncture stimulator on Arduino

The object of research is the electrical conductivity of biologically active points. Biologically active points as a method of non-traditional medical procedures and diagnostics, as well as being used for therapeutic purposes. Although this method has become the subject of mass research, a complete theory of the method has not yet been formed. Based on research, it is possible to say that there are different approaches to explaining the mechanism of action. These independent studies suggest the existence of unique electrical properties in the areas of the skin where biologically active points are located. However, due to technical and methodological problems, it was not in the interest of the scientific community, and as a result of solving the problem mentioned in recent history, interest in research in this field has increased. Nerve endings, called biologically active points or acupuncture points, are widely used in alternative medicine. The first step in electrostimulation of acupuncture points is the localization of the point. Localization is based on measuring the electrical conductivity of acupuncture points. The article discusses the virtual design of the measuring device, which is expected to be integrated with electrostimulators. As a result of the simulation, measurements were made and the accuracy class of the device was determined. Thus, it is possible to accurately measure electrical conductivity in biological objects through this device. The proposed device is designed on the basis of a modern element base. The basic element of the device is Arduino. A voltage divider scheme was used to determine the electrical conductivity of Arduino-based biologically active points. The purpose of using a voltage divider circuit is to protect the Arduino's analog input from overvoltage. Based on the measurements, the accuracy class of the proposed device was determined. As a result of the simulations, it was determined that the absolute error of the device is 0.463056, the relative error is 0.005742, and the accuracy class is 0.0463056.

Design of a Flying-Capacitor-Based Voltage Divider LLC Resonant Converter for USB-C PD Charger in Aircraft Applications

Portable electronic devices have grown dramatically at an incredible speed and include many new and sophisticated functions. Thanks to the advent of universal serial bus (USB) power delivery (PD) specifications, power delivery is increased as is the number of applications that can be powered using a USB cable in aircraft. However, the combination of the wide-voltage-gain operation required by the USB PD specification, high step-down ratio, and the lower-pressure environment associated with aircraft puts a lot of stress on converter optimization. This paper presents the DC-DC stage of an integrated, highly compact USB type-C PD charger for aircraft. First, a flying-capacitor-based voltage divider (FCVD) switching bridge is proposed to replace the conventional switching bridge in an LLC converter to improve its efficiency. Second, a printed circuit board (PCB) winding planar transformer is adopted to increase the power density. Gallium nitride devices are used for both the FCVD and the synchronous rectifiers, further shrinking the size and reducing the loss. Critical areas of the converter prone to a high electrical field (E-field) are identified and preemptively addressed with the use of the E-field control methodology that follows the Paschen-curve-based insulation coordination. The prototype is built and tested, and it is verified that the unit successfully operates in rated conditions to achieve a power density of 73.2 W/in <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> and an efficiency of over 90% at all nominal outputs. A high-altitude partial discharge test is also conducted, showing that the proposed prototype meets the partial discharge inception voltage (PDIV) at 10,000 ft.

Adaptive Level-Shift Gate Driver With Indirect Gate Oxide Health Monitoring for Suppressing Crosstalk of SiC MOSFETs

An adaptive level-shift gate driver with indirect gate oxide health monitoring for suppressing crosstalk of bridge-leg configured SiC MOSFETs is proposed. This paper firstly presents a holistic assessment of the changes in major intrinsic parameters before and after aging SiC MOSFETs with repetitive short-circuit tests. Gate leakage is found to be an appropriate precursor to reflect gate oxide degradation. Then, the structure, operation, and design of the proposed gate driver are given. The working principle is based on using a digitally controlled variable resistor in a resistor-capacitor-based voltage divider network to adjust the off-state gate-source voltage. Then, the peak off-state gate-source voltage caused by the spurious voltage is regulated at a level that can avoid shoot-through and reduce off-state voltage stress on the gate. Besides suppressing crosstalk, an optimal off-state gate-source voltage can also improve the life expectancy of SiC MOSFET. By utilizing the loading effect of gate leakage current on the proposed gate driver output, the gate oxide degradation is indirectly monitored by observing the change in the value of the variable resistor. The proposed gate driver has been evaluated on a 1kW inverter prototype under various intrinsic parameter variations. Performance comparisons between proposed and traditional gate drivers are given.

Characterization of a capacitive voltage divider

Voltage dividers are devices designed to reduce high voltages according to a transformation ratio to facilitate their measurement for different purposes. Among them is the detection of transient overvoltages in medium voltage lines. It is convenient to know the transformation ratio of the sensor and its working frequency range for the correct measurement of overvoltages. This article shows the characterization process of an air-insulated capacitive voltage divider used to measure induced voltages in distribution networks. A detailed description of the device is shown, such as how it works and the tests carried out for its characterization. The parameters of its equivalent circuit are obtained by modeling the voltage divider in the CST Studio 2021 software; through laboratory tests, its experimental transformation ratio is obtained; and through a frequency sweep applied to the divider, its frequency response is determined. Indeed, the experimental transformation ratio is 10667.46:1, and the frequency range obtained experimentally is between 60 Hz and 4 MHz, different data from those given by the manufacturer. These experimental data can be used as a reference for the capacitive voltage divider.

A Marx generator based on thyristors triggered in a shock ionization wave mode

Recently, a new trigger mode of thyristor which is called shock ionization wave mode is researched. Compared with the conventional trigger mode, this trigger mode can turn on the thyristor rather fast. In this mode, a trigger voltage with a high amplitude and fast rising speed is applied at both ends of the thyristor. Many single-tube conduction experiments are reported while the conduction threshold of shock ionization wave mode has not been investigated. Besides, the application of this trigger mode in some pulse power topology remains blank which is useful for this mode. In this paper, to explore the impact ionization wave mode conduction threshold of commercial thyristor, fast front high voltage nanosecond pulses are generated by avalanche tube Marx circuit. Pulse signals of different amplitudes are realized through the voltage division resistor. The impact ionization wave mode trigger threshold for commercial thyristors is about 2500 V in amplitude and 250 V/ns in voltage rising speed and the higher the rated parameter of the thyristor, the higher the threshold. To broaden the application of this mode, a novel Marx generator based on thyristors is proposed. A four-stage Marx generator is constructed and the amplitude of the output voltage can reach 1869 V.

Design and testing of circular metamaterial-based salinity sensors

The salinity sensor is a salt level detection tool designed based on the electrical properties of water. The salinity sensor consists of two electrodes that are dipped in water where the sensor is given a potential difference so that electrons flow in the sensor-building circuit. The electrode is connected to a variable resistor which forms a voltage divider circuit connection. This research aims to design a metamaterial (MTM) sensor to detect salt levels in the 100 – 900 MHz range and investigate the performance of MTM sensors for detecting salt levels. The working MTM sensor design has been successfully designed and tested, where the MTM sensor is also able to differentiate frequency values from samples with different salt levels.

Design of a Tomato Sorting Device Based on the Multisine-FSR Composite Measurement

The ripeness of tomatoes is crucial to determining their shelf life and quality. Most of the current methods for picking and sorting tomatoes take a long time, so this paper aims to design a device for sorting tomatoes based on force and bioelectrical impedance measurement. A force sensor installed on each of its four fingers may be used as an impedance measurement electrode. When picking tomatoes, the electrical impedance analysis circuit is first connected for pre-grasping. By applying a certain pre-tightening force, the FSR sensor on the end effector finger can be tightly attached to the tomato and establish an electric current pathway. Then, the electrical parameters of the tomato are measured to determine its maturity, and some of the electrical parameters are used for force monitoring compensation. Then, a force analysis is conducted to consider the resistance of the FSR under current stress. According to the principle of complex impedance circuit voltage division, the voltage signal on the tomato is determined. At the same time, the specific value of the grasping force at this time is determined based on the calibration of the pre-experiment and the compensation during the detection process, achieving real-time detection of the grasping force. The bioelectricity parameters of tomatoes can not only judge the ripeness of tomatoes, but also compensate for the force measurement stage to achieve more accurate non-destructive sorting. The experimental results showed that within 0.6 s of stable grasping, this system could complete tomato ripeness detection, improve the overall tomato sorting efficiency, and achieve 95% accuracy in identifying ripeness through impedance.

Voltage Reference Realignment Cell Balance to Solve Overvoltage Caused by Gradual Damage of Series-Connected Batteries

This paper analyzes the cause of electric vehicle battery fires. The fundamental cause is attributed to a low cell balance current, and it is proven that the variation in the battery’s internal voltage due to temperature change is the decisive reason for battery fires. In this paper, the authors studied a method of solving the problem by changing only the software of the existing Battery Management System (BMS) without changing the hardware. Batteries cannot be made with 100% capacity, resulting in voltage division. Cell balancing is performed to prevent such phenomena, but a low cell balance current prevents the proper operation of cell balancing. As a result, relatively small batteries, due to progressive degradation, have continuous voltage rise toward overvoltage. Subsequently, an additional voltage rise occurs as the chemical activity of the battery increases due to temperature rise. In this paper, a new cell balancing method is proposed to limit the aging process of cells with a relatively small capacity and peak voltage. In addition, it was validated through simulation using MATLAB R2019a.

Calculating a Resistive Voltage Divider for Insulated Neutral Networks

Calculating a Resistive Voltage Divider for Insulated Neutral Networks

Bioelectricity: A Top-Down Control Model to Promote More Effective Aging Interventions

Aging is a complex, multifaceted process that affects all organisms, characterized by functional decline and increased risk of death. Although the molecular and cellular basis of aging has been extensively studied, the roles of bioelectricity, biochemical gradients, and biomechanical gradients in this process remain less understood. This review investigates the current knowledge concerning these factors and their influence on aging at molecular, cellular, and whole organism levels. I examine the connection between steady-state membrane voltage (Vmem) and mitotic division, the relationship between mitochondrial membrane potential and aging, the role of epigenetic modifications in regulating gene expression, and the deliberate manipulation of bioelectric gradients to achieve desired outcomes in aging. This review emphasizes the need for further research to better comprehend the role of bioelectricity and chemical gradients in aging, and to identify potential targets for interventions to delay or alleviate the effects of aging.

Reconfigurable Antennas for RF Energy Harvesting Application: Current Trends, Challenges, and Solutions from Design Perspective

Due to the widespread use of low-power embedded devices in both industrial and consumer applications, research into the use of alternate energy sources has been sparked by the requirement for continuous power. Due to its accessibility and ability to be implanted, RF energy is always taken into consideration among the traditional energy sources that are currently available. There is a significant necessity for efficient RF front-ends, which must provide effective circular polarization (CP) features, effectiveness, feasibility from a design standpoint, and optimal usage of ambient RF signals accessible in the environment. So, for understanding their utilization in RF energy harvesting, a metasurface reflector-inspired CP-printed reconfigurable antenna integrated with a Greinacher voltage divider (GVD) rectifier circuit is reported. It offers broadband CP with fractional bandwidth &gt; 25%, CP gain &gt; 8.35 dBic, and directional radiation with the 3 dB angular beamwidth &gt; 100° in the 3.5/5 GHz bands. With the integration of the rectifier circuit, a theoretical DC output &gt; 4.8 V at 12 dBm is obtained. The acceptable impedance bandwidth, axial ratio bandwidth, antenna gain, antenna efficiency, and directional radiation with a 3 dB angular beamwidth value are studied and subsequently matched with the trade-offs (usage of diodes, complexity of DC biasing circuits, and attainment of polarization reconfigurability) obtained from the state of the art. A comprehensive study of the reconfigurable antennas is reported to highlight the findings as a widespread solution for these limitations in RF energy harvesting application.

An Insulation Monitoring Method for Transformer Windings Based on Electroluminescence Effect

Currently, the insulation monitoring method for transformer windings mainly monitors voltage, current, leakage inductance, leakage magnetic field, temperature, and dissolved gas in oil. However, these methods often have the disadvantages of low sensitivity, inability to locate, and slow response time. This paper presents a novel insulation monitoring method for transformer windings based on electroluminescence. In this method, electroluminescent coatings are sprayed on the sides of the blocks between pancake windings. The electric field intensity between the windings is measured according to the coating’ luminance, then the winding insulation state is monitored, and faults can be located. To verify this method, we make a transformer winding model based on the principle of capacitive voltage division. Interturn and interlayer insulation faults are simulated by changing capacitors. The results show that the method has an error of less than 3% in measuring the electric field between transformer pancake windings and is feasible for transformer winding insulation monitoring. In addition, this method also can be used for the detection of transformer winding deformation.

Design of an Intelligent MEMS Safety and Arming Device with a Condition Feedback Function.

A safety and arming device with a condition feedback function has been designed in this article to improve the intelligence and safety of ignition devices. The device achieves active control and recoverability by virtue of four groups of bistable mechanisms which consist of two electrothermal actuators to drive a semi-circular barrier and a pawl. According to a specific operation sequence, the barrier is engaged by the pawl at the safety or the arming position. The four groups of bistable mechanisms are connected in parallel, and the device detects the contact resistance generated by the engagement of the barrier and pawl by the voltage division of an external resistor to determine the parallel number of the mechanism and give feedback on the device's condition. The pawl as a safety lock can restrain the in-plane deformation of the barrier in the safety condition to improve the safety function of the device. An igniter (a NiCr bridge foil covered with different thicknesses of Al/CuO films) and boron/potassium nitrate (B/KNO3, BPN) are assembled on both sides of the S&A device to verify the safety of the barrier. The test results show that the S&A device with a safety lock can realize the safety and arming functions when the thickness of the Al/CuO film is set to 80 μm and 100 μm.

Implementation of PSO algorithm on MPPT PV System using Arduino Uno under PSC

The availability of fossil energy sources decreases as consumers' demand for electrical energy increases rapidly. Currently, the utilization of renewable energy sources is crucial. PV is a renewable energy source that converts photon energy into DC current. Maximum power point tracker (MPPT) control technology for photovoltaics has advanced significantly. PV is unique in that its P-V characteristic curve is non-linear. Conditions of partial shading can cause the P-V curve to have multiple peaks. This research will design MPPT PV using the Particle Swarm Optimization (PSO) algorithm in partially shaded conditions with an Arduino Uno and boost converter. Conventional algorithms, incremental conductance (IC), and Perturb and Observe (P&amp;O) are implemented as a comparison. The purpose of implementing the PSO algorithm is to find the global peak of power to minimize power losses of PV. It leads to optimal power in case of partial shading conditions. Two PV modules are arranged in series for MPPT in a partially shaded environment. The examination was conducted in a darkened room with spotlights. The mean absolute percentage error of the current sensor, INA219, and the voltage sensor, voltage divider, was less than 1% during testing. The MPPT PV system test results indicate that the PSO algorithm can extract approximately 1.64 Watts of average power. In contrast, the IC and P&amp;O algorithms can extract about 1.25 Watts and 1.41 Watts, respectively. When no algorithm exists in the control system, the extracted power is approximately 1.13 watts. Thus, the PSO algorithm tracks global or optimal power under partial shading conditions.

A novel AC flatness adjustment technique for wideband resistive voltage dividers

Resistive voltage dividers (RVDs) are commonly used as AC attenuation networks in measurement circuits; however, their high-frequency gain is always disturbed by nasty parasitic elements and deviates significantly from the desired design value. This paper proposes a closed-loop adjustment technique for adjusting the frequency response flatness of wideband RVDs (WRVDs). In the proposed adjustment scheme, the frequency response flatness of the WRVD is determined by a voltage-controlled compensation capacitor, whereas the corresponding control voltage is provided by a digital potentiometer. The settling time and the adjustment error of the loop are analyzed to evaluate the adjustment performance. To verify the concept, the adjustment loop is incorporated into a 100:1 WRVD for demonstration. Final experiments show that the proposed technique improves gain flatness by 81 times compared with uncompensated flatness, with 1.15% up to 2MHz, and that the compensated voltage divider has an excellent linearity of 36 ppm up to 100V.

Calibration of UHV Impulse Voltage Divider in China

This article proposes the necessity of reliable calibration of the high voltage impulse value and the difficulty for accurate metrology work. It outlines the problems for common linearity test methods for impulse voltage dividers and the recent research work in China for lightning impulse voltage dividers calibration.

Harmonic-Reduced Bias Circuit for Ultrasound Transducers.

The gain of class-C power amplifiers is generally lower than that of class-A power amplifiers. Thus, higher-amplitude input voltage signals for class-C power amplifiers are required. However, high-amplitude input signals generate unwanted harmonic signals. Therefore, a novel bias circuit was proposed to suppress the harmonic signals generated by class-C power amplifiers, which improves the output voltage amplitudes. To verify the proposed idea, the input harmonic signals when using a harmonic-reduced bias circuit (-61.31 dB, -89.092 dB, -90.53 dB, and -90.32 dB) were measured and were found to be much lower than those when using the voltage divider bias circuit (-57.19 dB, -73.49 dB, -70.97 dB, and -73.61 dB) at 25 MHz, 50 MHz, 75 MHz, and 100 MHz, respectively. To further validate the proposed idea, the pulse-echo measurements were compared using the bias circuits. The peak-to-peak echo amplitude and bandwidth of the piezoelectric transducer, measured when using a harmonic-reduced bias circuit (27.07 mV and 37.19%), were higher than those achieved with a voltage divider circuit (18.55 mV and 22.71%). Therefore, the proposed scheme may be useful for ultrasound instruments with low sensitivity.