Measurement Of Electrical Parameters Research Articles

Development and application of Sequencing Batch Airlift Reactor for Domestic Sewage Treatment

Aiming at the demand of decentralized domestic sewage treatment in rural areas, Sequencing Batch Airlift Reactor (SBAR) for domestic sewage treatment was developed and applied for sewage disposal of an office building in shenjiadun village, Deqing, Zhejiang Province. The device doesn’t need to set up sedimentation tank and sludge reflux system. It has a good precipitation effect and only occupies a small area. In the aspect of control, it adopts the self-researched embedded software system. And it integrates GPRS/GSM/SMS/CDMA/Internet communication technology and high-precision electrical parameter measurement technology. The actual operation results show that the device can ensure sufficient contact between sludge and waste water. It can effectively remove BOD5, CODCr, ammonia nitrogen and total nitrogen from domestic sewage. And it has the advantages of low investment, low energy consumption, high automation and simple operation. Therefore, this device has important popularization value in the field of distributed treatment of rural domestic sewage.

Influence of low ambient pressure on the performance of a high-energy array surface arc plasma actuator

In order to solve the problem of single arc plasma actuator’s failure to suppress the boundary layer separation, the effectiveness of the array surface arc plasma actuator to enhance the excitation intensity is verified by experiment. In this study, an electrical parameter measurement system and high-speed schlieren technology were adopted to delve into the electrical, flow field, and excitation characteristics of the high-energy array surface arc plasma actuator under low ambient pressure. The high-energy array surface arc discharge released considerable heat rapidly; as a result, two characteristic structures were generated, i.e., the precursor shock wave and thermal deposition area. The duration increased with the increase in environmental pressure. The lower the pressure, the wider the thermal deposition area’s influence range. The precursor shock wave exhibited a higher propagation speed at the initial phase of discharge; it tended to decay over time and finally remained at 340 m/s. The lower the environmental pressure, the higher the speed would be at the initial phase. High-energy array surface arc plasma actuator can be employed to achieve effective high-speed aircraft flow control.

Online Condition Monitoring for Bond Wire Degradation of IGBT Modules in Three-Level Neutral-Point-Clamped Converters

In this article, an online condition monitoring (CM) method is proposed for the bond wire degradation of insulated-gate bipolar transistor (IGBT) modules in a single-phase or three-phase three-level neutral-point-clamped (3LNPC) dc-ac, ac-dc converter. The proposed method has the ability to detect the whole IGBTs in a 3LNPC converter, based on finding the idle on-state IGBTs under the specific load current direction and switching sequence of a leg. The detection time is short (0.2 ms) and the influence of online CM on load current can be completely neglected as long as the insertion areas for CM test are chosen reasonably. Meanwhile, an advanced bond wire CM module is designed to conduct the CM test. This module can generate and inject the current pulse trains into IGBT modules, with the high current for CM test and low current for temperature-sensitive electrical parameter measurement, and sample the collector-emitter on-state voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CE</sub> _ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> ) stably and precisely. Finally, the experimental work was carried out to verify the effectiveness of the proposed method and the practicality of the developed CM module.

Eco-Friendly Fully Water-Driven HfGdO${_{x}}$ Gate Dielectrics and Its Application in Thin-Film Transistors and Logic Circuits

In this work, HfGdO x gate dielectric thin films have been prepared via a nontoxic and environmental-friendly fully water-driven (WD) method. An in-depth investigation has been conducted to reveal the evolution of physical properties in the as-prepared HfGdO x thin films as a function of annealing temperature. Based on the measurements of electrical parameters of the HfGdO x thin films, it is observed that the 500 °C-annealed HfGdO x thin films have shown optimized properties, including a smooth surface, lower leakage current density, and a larger areal capacitance. To validate the feasibility of the HfGdO x gate dielectrics in thin-film transistors (TFTs), In2O3/HfGdO x TFTs have been constructed. The optimized In2O3/HfGdO x TFT exhibited excellent electrical performances, including high field-effect mobility of 11.2 cm2 V−1 s−1, a high ON-/OFF-state current ratio of ${4.1} \times {10}^{{6}}$ , a small sub-threshold swing of 105.2 mV/decade, and a threshold voltage shift of 0.58 V after 7200-s bias stress, respectively. Finally, based on the In2O3/HfGdO x TFT, an inverter is assembled by connecting an external 3- $\text{M}\Omega $ resistor. High gain of 8.73 and excellent swing characteristics have been obtained. As a result, it can be inferred that fully WD In2O3/HfGdO x TFTs with high performance will pave the way for achieving low-power-consumption, low-cost, and large-area electronics.

Methods of computer tools development for measuring and analysis of electrical properties of semiconductor films

The method is presented and computer tools of automated measurement of electrical parameters and experimental data processing are developed, taking into account models for describing physical processes that determine the operating characteristics of semiconductor material. The possibility of automated investigation of the quality and ohmicity of contacts is realized, which significantly improves the reliability of the data obtained.Methods and features of software processing of automated research results are considered using the models that allow taking into account the effect of surface, structure and thickness of the sample on the electrical properties of semiconductor films.Experimental studies of a series of n-PbTe thin films are carried out and the efficiency of the developed tools and methods of processing scientific data using the described methods of experimental data analysis is shown. Based on the simulation, the electrical parameters of the surface layers were determined and the effect of the surface and grain boundary mechanisms of charge carrier scattering on the electrical parameters of the films was separated. The surface mobility of the charge carriers is approximately 3 times less than the mobility in the bulk material, which indicates the dominance of the diffuse scattering of charge carriers on the surface of the thin-film samples despite the high reflectance coefficient (0.4). Taking into account the effect of the surface and the boundaries of the grains, it is possible to choose the technological modes and duration of spraying to obtain a semiconductor material with the desired properties.As a result of using the developed tools, it was possible to significantly reduce the complexity of the process of measuring the basic electrical parameters of semiconductor materials, processing the experimental results, to improve the accuracy of the results obtained

Обеспечение электромагнитной совместимости морской техники при возникновении электростатических разрядов

The paper describes the problem of electromagnetic compatibility for electrostatic discharge (ESD), which is most actual for ships where all systems are highly automated and susceptible to ESD digital technology. The results of electromagnetic compatibility tests of ship systems after their installation on the vessel allow to conclude that it is not enough to fulfill only the existing ESD immunity requirements of the Russian Maritime register of shipping which are currently confirmed by ESD tests in the laboratory. ESD methods and reasons have been analyzed. The possible accumulated potentials and parameters of currents, voltages and field strengths during discharge are presented. The existing ESD immunity standards are being considered. The scheme of the developed and certified generator of electrostatic discharges ESD – 25000 is presented. The most frequent defects under the influence of ESD are given. There have been formulated the equivalent schemes of the electric equipment housing at different lengths of grounding of the housing and the methods of connecting the cover with the housing. The results of measurements of electric field and magnetic field parameters are presented. The results of modeling and experiments are compared. The developed sensors, methods of their calibration and obtained technical characteristics are being tested. There are given the parameters and forms of ESD voltage and current, experimental data of ESD secondary effects in the EE hull and adjacent equipment, results of discharges in the ship's cable, interference in the supply network through secondary power sources. The most effective design and ESD protection methods have been analyzed

The Discharge Preceding the Intense Reillumination in Positive Leader Steps Under the Slow Varying Ambient Electric Field

AbstractUnder the slow varying ambient electric field, positive leader propagation exhibits steps characterized by intense reilluminations and abrupt elongations. These steps are currently not well understood. In this work, we investigate these steps in laboratory atmospheric discharges, using a high‐speed video camera and a synchronized electrical parameter measurement system. The discharge, emitting weak light and preceding the intense reillumination, is discovered. This finding suggests that the leader channel actually restarts and extends forward before the intense reillumination, which deepens our understanding of the dynamic process of the positive leader step. The discharge before the intense reillumination contributes to the corona inception from the electrode, leading to the intense reillumination of the leader channel and the emergence of an intense corona streamer burst from the leader tip.

Ussing Chamber Methods to Study the Esophageal Epithelial Barrier.

The Ussing chamber was developed in 1949 by Hans Ussing and quickly became a powerful tool to study ion and solute transport in epithelia. The chamber has two compartments strictly separating the apical and basolateral sides of the tissue under study. The two sides of the tissue are connected via electrodes to a modified electrometer/pulse generator that allows measurement of electrical parameters, namely, transepithelial voltage, current, and resistance. Simultaneously, permeability of the tissue to specific solutes or markers can be monitored by using tracers or isotopes to measure transport from one side of the tissue to the other. In this chapter, we will describe the use of the Ussing chamber to study the barrier properties of the mouse esophageal epithelium. We will also briefly describe the use of the modified Ussing chamber to simultaneously study transepithelial and cellular electrophysiology in the rabbit esophageal epithelium. Lastly, we will cover the use of the Ussing chamber to study bicarbonate secretion in the pig esophagus. These examples highlight the versatility of the Ussing chamber technique in investigating the physiology and pathophysiology of epithelia including human biopsies.

Experimental study on supersonic plate boundary layer transition under pulsed arc plasma excitation control

Pulsed arc plasma excitation is characterized by strong local heating effect and wide disturbance range, and it has a broad application prospect in supersonic flow control. In this paper, by using electrical parameter measurement system and high speed schlieren technique, we study the electrical and flow field characteristics of pulsed arc plasma excitation under the condition of &lt;i&gt;Ma&lt;/i&gt; = 3 incoming flow. The nano-particle planar laser scattering (NPLS) is used to investigate the flow structure of the supersonic flat boundary layer, and the transition characteristics of the boundary layer at different plasma excitation frequencies are studied. The experimental results show that in the flow field with &lt;i&gt;Ma&lt;/i&gt; = 3 and the total incoming pressure &lt;i&gt;P&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt; = 1 atm (1 atm = 1.01 × 10&lt;sup&gt;5&lt;/sup&gt; Pa), the peak voltage of the pulsed arc plasma actuator discharge is 6 kV, the peak current is 70 A, the time scale of the discharge is about 300 ns, the single discharge energy is 70 mJ; the pulsed arc discharge will produce the precursor shock wave with higher velocity and the thermal deposition zone with higher temperature, which will exert continuously disturbance on the boundary layer. The pulsed arc plasma excitation with perturbation can promote the transition of supersonic plate boundary layer. Moreover, the high-frequency impact effect of pulsed discharge can promote the transition to occur ahead of time, and the higher the frequency, the better the effect is. As the excitation frequency increases, the transition position of the boundary layer of the supersonic flat plate moves forward, and the length of the transition area of the boundary layer becomes shorter as the excitation frequency increases. When the excitation frequency is 60 kHz, the length of transition zone is 0 and the thickness of turbulent boundary layer is 25 mm. When a high frequency is applied (&lt;i&gt;f&lt;/i&gt; = 40, 60 kHz), the transition path of the boundary layer is that the shock wave generated by the plasma excitation triggers the unstable wave, and the development of unstable waves directly skips the linear growth stage, passes through the bypass and transitions into turbulent flow. The pulsed arc plasma excitation can be used to promote supersonic boundary layer transition.

Contingency-based Voltage Stability Monitoring via Neural Network with Multi-level Feature Fusion

To monitor the voltage stability state of complex power grid, a four-category stability classification problem that incorporates a set of serious contingencies is posed. Quick decision-making and high accuracy are critical for the safety operation of power system. However, this problem involves feature of different types, levels and dimensions and is hard to be handled by the traditional classifier. This paper utilizes the deep learning technique and proposes a multi-level deep neural network (ML-DNN) that achieves feature fusion of the electrical parameter measurements, topology and contingency information. experiments are implemented on IEEE-39 system, the ML-DNN performs better in four main evaluation indices comparing with five existing models, which demonstrates its advantage for online voltage stability monitoring.

Developing Computational Intelligence for Smart Qualification Testing of Electronic Products

In electronics manufacturing, the necessary quality of electronic components and parts is ensured through qualification testing using standards and user requirements. The challenge is that product qualification testing is time-consuming and comes at a substantial cost. The work contributes to develop a novel prognostics framework for predicting qualification test outcomes of electronic components enabling the reduction of qualification test time and cost. The research focuses on the development of a new, prognostics-based approach to qualification of electronics parts that can enable “smart testing” using data-driven modelling techniques in order to ensure product robustness and reliability in operation. This work is both novel and original because at present such approach to qualification testing and the associated capability for test time reduction (respectively cost reduction) it offers are non-existent in the electronics industry. An effective way of using three different methods for development of prognostics models are identified and applied. Predictive models are constructed from historical qualification test data in the form of electrical parameter measurements using Machine Learning (ML) techniques. ML models can be imbedded within the sequential electrical tests qualification procedure and enable the forecasting of the pass/fail qualification outcome using only partial information from already completed electrical tests. Data-driven prognostics models are developed using the following machine learning techniques: (1) Support Vector Machine (SVM), (2) Neural Network (NN) and (3) K-Nearest Neighbor (KNN). The results show that with just over half of the individual tests completed, the models are capable of forecasting the final qualification outcome, pass or fail, with accuracy as high as 92.5%. The predictive power and overall performance of the researched models in predicting qualification test binary outcomes with varying ratios of Pass and Fail data in the processed datasets are analysed.

A Novel Method for Notable Reducing Phase Transition Temperature of VO2 Films for Smart Energy Efficient Windows.

Although Vanadium dioxide (VO2) has a potential application value for smart energy efficient windows because of its unique phase transition characteristic, there are still many obstacles that need to be overcome. One challenge is to reduce its high transition temperature (ζc = 68 °C) to near room temperature without causing its phase transition performance degradation. In this paper, a novel method was employed that covered a 3 nm ultra-thin heavy Cr-doped VO2 layer on the pure VO2 films. Compared with the as-grown pure VO2, obviously, phase transition temperature decreasing from 59.5 °C to 48.0 °C was observed. Different from previous doping techniques, almost no phase transition performance weakening occurred. Based on the microstructure and electrical parameters measurement results, the mechanism of ζc reducing was discussed. The upper ultra-thin heavy Cr-doped layer may act as the induced role of phase transition. With temperature increasing, carrier concentration increased from the upper heavy Cr-doped layer to the bottom pure VO2 layer by diffusion, and induced the carrier concentration reach to phase transition critical value from top to bottom gradually. The present method is not only a simpler technique, but also avoids expensive alloy targets.

Monitoring and Controlling Electric Power Stations Using GSM Network

This paper introduces a system design for monitoring and controls the components of power generation station and substation with help of existing communication link based on GSM network. In this design, a selected Programmable Logic Controller (PLC) connected to the fields that needed to be monitored and continuously read changes in measurements of electrical parameters like voltage, current, bus bar circuit breakers…..etc.. These parameters have been monitored by PLC, on the base of conditions that PLC is programmed. PLC generates a text message and forward to other side; control center or mobile phone of engineer and technicians; who are responsible of monitoring. At control center, another GSM modem which has capability to connect with personal computer, receives that text massage using SMS and executes it. Software written with Vb.Net, works as Human Machine Interface (HMI) for this purpose. The system performance is acceptable in terms of errors in readings and time delay. The percentage error for the current is about 1%, and for the voltage is about 0.2%. The delivery time to receive new analog and digital inputs data is about 14.125 seconds, while the control of the circuit done after 4.68 seconds.

Análisis de la calidad de energía eléctrica en una subestación de 300 kVA

In this research are presented the results of the measurements of the electrical parameters obtained by the three phase analyzer of electrical energy, there was used a methodology based on the own manual of the analyzer equipment, well as the national and international standards as well the IEEE Institute, the CFE company, and books of the subject, in which are stablished the limits and requirements for a good quality of the electrical energy necessary for the user of the electrical service. The contribution covers from the conection of the entry of the analyzer equipment until the instalation to the exit of low tension in the transformer, verifying in the equipment the vectorial diagrams and senoidals for corroborate that their conection be adequate, also were considered the measurements of the security in the instalation of the measurement equipment, throughout the document are mentioned the characteristics and the interpretation of each electrical parameter analyzed.

Energy Optimization of Bharati Vidyapeeth (Deemed to be) University Dhankawadi Campus Pune, INDIA

This paper represents “Energy Optimization of Bharati Vidyapeeth (deemed to be) university Dhankawadi campus Pune, India”. Generally Educational Institutions are not taken into consideration for energy optimization in our country and around the world which comes in commercial sector. The energy cost is to be managed in academic campus to control the budget and utilize that amount for the growth of the institute. Around10 to 30% of the energy can be saved in academic campus. The objective of this study is to highlight several opportunities in creating and implementing energy optimization plans within the campus. The current pattern of energy use and safety concern is taken into account. Power quality analyzer is used for measurement and analysis of various electrical parameters at all five substations. Some suggestions are given for efficient use of energy and get benefited for new billing pattern of distribution authorities. The installed electrical facilities and their requirements are taken care like Transformer, APFC panel and capacitors used in the APFC panel.

Electrical characterization of the root system: a noninvasive approach to study plant stress responses

A pot experiment was designed to demonstrate that the parallel, single-frequency detection of electrical capacitance (CR), impedance phase angle (ΦR), and electrical conductance (GR) in root–substrate systems was an adequate method for monitoring root growth and some aspects of stress response in situ. The wheat cultivars ‘Hombar’ and ‘TC33’ were grown in a rhyolite-vermiculite mixture under control, and low, medium, and high alkaline (Na2CO3) conditions with regular measurement of electrical parameters. The photochemical efficiency (Fv/Fm) and SPAD chlorophyll content were recorded non-intrusively; the green leaf area (GLA), shoot dry mass (SDM), root dry mass (RDM), and root membrane stability index (MSI) were determined after harvest. CR progressively decreased with increasing alkalinity due to impeded root growth. Strong linear CR–RDM relationships (R2 = 0.883–0.940) were obtained for the cultivars. Stress reduced |ΦR|, presumably due to the altered membrane properties and anatomy of the roots, including primarily enhanced lignification. GR was not reduced by alkalinity, implying the increasing symplastic conductivity caused by the higher electrolyte leakage indicated by decreasing root MSI. Fv/Fm, SPAD value, GLA, and SDM showed decreasing trends with increasing alkalinity. Cultivar ‘TC33’ was comparatively sensitive to high alkalinity, as shown by the greater relative decrease in CR, SDM, and RDM under stress, and by the significantly lower MSI and higher (moderately reduced) |ΦR| compared to the values obtained for ‘Hombar’. Electrical root characterization proved to be an efficient non-intrusive technique for studying root growth and stress responses, and for assessing plant stress tolerance in pot experiments.

Mathematical correlations between selected quality attributes and electrical parameters of apple juice

This study aimed at determining mathematical correlations between total soluble solids (TSS) content, content of organic acids (OA), pH value (pH), and density (D) of apple juice and their electrical conductance and capacitance using the RCC equivalent model of food products (resistance and capacitance). Linear correlations were determined between total soluble solids content, organic acids content, and density of aqueous solutions of the apple juice concentrate and values of their impedance (Z) and admittance (Y) in a frequency from 100 to 100,000 Hz; and their equivalent parallel capacitance (Cp) at frequencies of 100, 120, and 1,000 Hz; as well as their equivalent series capacitance (Cs) at frequency of 100,000 Hz. It was concluded that the correlations obtained from grounds for future studies on the development of a method for detecting adulterations (through watering) of apple juices based on measurements of electrical parameters, including the impedance or admittance. Practical applications Due to increasing requirements for the food quality and safety, as well as an increased demand for apple juice, many research works on the development of modern techniques for identification, detection of adulteration, and predicting its quality have been undertaken. Taking this into account, the research was undertaken to determine the mathematical relationships between selected quality attributes of apple juice (TSS, organic acids, pH, density) and their electrical parameters. The obtained significant mathematical correlations (r > 0.87 and p ≤ 0.01), indicate that the quality of apple juices can be predicted on the basis of simple impedance and admittance measurements at f = 100 Hz. These dependencies also justify the use of the RCC electric model for predicting the basic attributes of the apple juice quality, which in the future will make possible the development of a method for detecting its adulteration with water. On this basis, a relevant patent has been yet obtained.

POWER MODEL OF IMPULSE ARC DISCHARGE GENERATION IN ACTIVE MEDIA OPTICAL PUMPING XENON LAMPS OF SOLID-STATE LASERS

The semi-empirical model of arc impulse discharge development in impulse xenon lamps for optical pumping of solid-state lasers' active media was considered. Equations of the power balance of supplied electrical power and processes of ionization, plasma heating, heat dissipation and optical radiation generation laid the model's basis. The analytical description of the processes being considered results in an ordinary differential equation which allows a non-resource-intensive numerical solution. The built model enables to evaluate basic electrical and optical parameters of non-local arc discharge plasma at its development stage. Comparison with the results of measurements of electrical and optical plasma parameters which are the most convenient for experimental diagnostics in the modelled non-stationary mode testifies to adequacy of the developed model. Relative simplicity and convenience of the model predetermines its possible usage when solving applied engineering tasks of optimization of operating parameters of impulse pumping lamps and for obtaining initial (zero) approximations for comprehensive modelling of a non-local non-stationary gas discharge plasma in science-intensive calculations taking into account a great combination of elementary collision and radiation processes in a non-equilibrium system.

Monitoring the state of the secondary circuits of contact machines in conditions of mass production

ABSTRACT A measuring method the active resistance of the secondary contours of multi-electrode resistance welding machines working in mass production is proposed and tested, which makes it possible to track the need to replace their elements. The method provides the periodic switching on the machine in the short circuit mode, the measurement of electrical parameters and the calculation by approximating the dependence of the active resistance of the secondary circuit. The need to replace the elements of the secondary circuit is established by a sharp increase in the rate of change (in time) of active resistance.

Applicability of Measurements of Local Electrical Parameters in the Modeling of Technological Texture of Ceramic Blanks

The paper deals with the modeling of the technological texture of the pressed ceramic materials in the radial and axial direction, which consists in the graphical representation and subsequent analysis of the distribution of the electrostatic field potential differences on the surface of the dielectric sample with the diameter d and the thickness h located between the electrodes. In occasion of observing radial texture the electrodes have the cylindrical configuration and in occasion of observing the axial texture in the sample the electrodes have the axial configuration. The theoretical relationship in the paper is derived for the calculation of the voltage values measured at any position between the center electrode and the peripheral electrode, at a constant voltage U applied to the outer and inner electrodes of the dielectric sample of thickness h of the raw ceramic sample material (radial texture). Measurements have demonstrated the suitability of identifying the technological texture by measuring the potential differences on the sample surface which is located between the electrodes in the relation to the technology preparation and to the quality of the fired ceramic production.