Performance test of small-current grounding line selection device based on the real-time digital simulation system

Single phase grounding fault is the most common fault type in small-current grounding distribution network, but the small-current grounding line selection device put into operation on site is often difficult to meet the application requirements, affecting the rapid and accurate treatment of grounding fault. Considering that there are many small-current grounding line selection manufacturers and various device forms, it is difficult to intuitively evaluate the line selection performance of different devices and make horizontal comparison, and there is no supporting basis for the selection and application of on-site line selection devices. Therefore, based on the real-time digital simulation system (RTDS), this paper establishes a test platform for small-current grounding line selection device. Based on the constructed test platform, four line selection devices form different manufacturers are tested in parallel, the performance of the devices is compared, and the influencing factors affecting the accuracy of line selection results are analyzed. The conclusions of this paper can provide strong support for the pilot application of small-current line selection devices.

Effect of extinction beam-plasma discharge while the injection thermoelectrons during transportation of the electron beam in the forevacuum pressure range

The article presents the results of experiments aimed at studying the effect of low-energy thermoelectrons on the parameters of the beam plasma and plasma of the beam-plasma discharge generated during the transportation of a powerful electron beam in the pressure range of the medium vacuum. It is shown that the injection of a sufficiently small current of low-energy thermoelectrons is capable of violating the conditions for the combustion of the beam-plasma discharge and reducing the power loss of the electron beam for SPR generation. In this case, the plasma concentration decreases by almost an order of magnitude (to 1015 m–3) and the temperature of plasma electrons decreases by almost three (to 0.3 eV).

Research on electrodermal activity

In this chapter, a method of physiological measurements—that is detection of electrodermal activity based on the sectonic activity of eccrine sweat glands—is discussed. It is believed that the excretion of sweat, which is regulated by the nervous system acting independently of human will, is an indicator of a person’s emotional arousal as a result of specific stimuli. Hence, the electrodermal reaction can be used in diagnosing emotional arousal caused by, e.g. specific products, advertisements or elements of the in-store space. Electrical activity of the skin is caused by two types of stimuli: sustained and one-off. Sustained stimuli have a continuous effect on the body over a relatively long period of time. On the other hand, one-off stimuli have a relatively strong and very short-lasting effect. This type is defined as novel, unexpected, significant or aversive. Electrodermal activity is measured on the skin surface (Strelau, 2006). Generally speaking, the measurement of electrodermal activity is one of the biometric measurements. Biometrics is a universal term that represents measurements of the body’s physiological responses—not directly of the brain—to external stimuli that are felt through the senses (Pradeep, 2010; Berčík & Rybanská, 2017). The electrodermal method allows to measure either electrical resistance or its inverse, i.e. the electrical conductivity of the skin. These measurements are carried out while a small current flows through the skin from an external source. Electrodermal activity measurement is performed with the use of special electrodes, electrode gels and recording devices. The available equipment for the analysis of electordermal activity is characterised by relatively low cost (compared to other devices for physiological measurements)of purchase and operation. Moreover, the electrodermal activity measurement is non-invasive and carries no risk to the health or life of the test subjects.

A Novel Approach to Investigate Analog and Digital Circuit Applications of Silicon Junctionless-Double-Gate (JL-DG) MOSFETs

The double gate junctionless transistor (DG-JLT) has become the most promising device in sub nano-meter regime. DGJLT based circuits have improved performance and simpler fabrication than their inversion mode counterparts. This paper demonstrates the design of different analog and digital circuits using DGJLT. Amplifiers and inverters are the basic building block of electronic ICs. A MOS amplifier converts the variation of the gate to source voltage to a small current under transconductance and hence, the output voltage. A single-stage amplifier and differential amplifier have been designed with junctionless-double-gate (JL-DG) MOSFET. Trans-conductance, output voltage, and gain have been investigated using ATLAS 2D device simulator. The inverter is the primary logic gate that can be used to verify the device's response in digital applications. Further, CMOS inverter have been designed using JL-DG MOSFET, and its performance parameters such as switching voltage, noise margin, and logic delay have been analyzed. A switching voltage of 0.43 V, noise margin of 0.265 V, and a delay of 19.18 psec have been obtained for the basic cell. CMOS inverter using JL-DG MOSFET at 20 nm technology node have prompted better performance results. Thus, The JL-DG MOSFET has a bright future in low-power analog and digital applications.

Ceria Particles as Efficient Dopant in the Electrodeposition of Zn-Co-CeO2 Composite Coatings with Enhanced Corrosion Resistance: The Effect of Current Density and Particle Concentration

Novel Zn-Co-CeO2 protective composite coatings were deposited successfully from chloride plating solutions. Two different types of ceria sources were used and compared: commercial ceria powder and home-made ceria sol. Electrodeposition was performed by a direct current in the range of 1–8 A dm−2. Two different agitation modes were used and compared, magnetic stirring and ultrasound-assisted stirring (US). The influence of magnetic stirring on the stability of the related plating baths was evaluated via a dynamic scattering method. The results pointed to better stability of the prepared ceria sol. The morphology of the composite coatings was examined by scanning electron microscopy (SEM), and particle content was determined by energy-dispersive X-ray spectroscopy (EDS). The results showed that the increase in the deposition current density was not beneficial to the coating morphology and particle content. The corrosion behavior of the Zn-Co-CeO2 composite coatings was analyzed and compared by electrochemical impedance spectroscopy and polarization resistance. The ultrasound-assisted electrodeposition at small current densities was favorable for obtaining composite coatings with enhanced corrosion stability. The protection was more effective when US was applied and, additionally, upon utilization of ceria sol as a particle source, which was revealed by higher polarization resistance and greater low-frequency impedance modulus values for sol-derived composite coatings deposited under ultrasound.

Small Current Fault Line Selection Based on Improved Empirical Mode Decomposition and Fractal Dimension Method

In this paper, the fault steady state and transient characteristics of small current grounding system are analyzed, and the distribution of transient zero sequence current is introduced. A fault line selection based on EMD and fractal dimension method is proposed. After the parameter is determined, the problem is proposed and improved. Using the simulated annealing K-means algorithm to find the scale-free interval curve to get the line slope is the correlation dimension of the line. Finally, by comparing the size of the associated dimension, you can select the corresponding line of the faulty distribution network.

Numerical Investigation of an Experimental Ocean Current Turbine Based on Blade Element Momentum Theory (BEM)

Ocean currents are one of the alternative sources of green, sustainable, and renewable energy that could generate low-cost electric power without any pollution due to the burning of fossil fuels. Due to the density of the water, ocean currents can produce a significant amount of energy even with a very small current velocity field. In this study, a comprehensive performance analysis of 3-blade horizontal-axis Ocean Current Turbine (OCT) is shown to achieve optimal rpm (revolutions per minute) to match environmental conditions in order to harvest the maximum possible energy from OCT in ocean currents. Our approach is to use Blade Element Momentum (BEM) theory in order to estimate hydrodynamic loads for the turbine; specifically, the design of the OCT blades is based on a FX77-W121 type airfoil. We use JavaFoil to analyze and determine hydrodynamic lift and drag coefficients with respect different angles of attack for the hydrofoil profiles in seawater. After validation of blade design characteristics and obtaining the local coefficients of each hydrofoil cross-sections, we transfer them to our in-house-developed Blade Element Momentum Theory (BEM) code in order to achieve the estimation of performance analysis of the OCT in order to get maximum power and ideal torque and thrust. This performance analysis with BEM model of the OCT is an important step for further analysis due to having different incoming flow speeds in actual time-varying sea conditions. Indeed, the OCT will encounter different incoming ocean current speeds during operation. Therefore, this approach is used to get an accurate brake power estimate of the OCT in different operational current speeds. In addition, this performance analysis of the OCT is going to be utilized in designing and developing a test model for the physical towing tank experiment for later investigation.

Structure-Property Relation of Trimethyl Ammonium Ionic Liquids for Battery Applications

Ionic liquids are attractive and safe electrolytes for diverse electrochemical applications such as advanced rechargeable batteries with high energy densities. Their properties that are beneficial for energy storage and conversion include negligible vapor-pressure, intrinsic conductivity as well as high stability. To explore the suitability of a series of ionic liquids with small ammonium cations for potential battery applications, we investigated their thermal and transport properties. We studied the influence of the symmetrical imide-type anions bis(trifluoromethanesulfonyl)imide ([TFSI]−) and bis(fluorosulfonyl)imide ([FSI]−), side chain length and functionalization, as well as lithium salt content on the properties of the electrolytes. Many of the samples are liquid at ambient temperature, but their solidification temperatures show disparate behavior. The transport properties showed clear trends: the dynamics are accelerated for samples with the [FSI]− anion, shorter side chains, ether functionalization and lower amounts of lithium salts. Detailed insight was obtained from the diffusion coefficients of the different ions in the electrolytes, which revealed the formation of aggregates of lithium cations coordinated by anions. The ionic liquid electrolytes exhibit sufficient stability in NMC/Li half-cells at elevated temperatures with small current rates without the need of additional liquid electrolytes, although Li-plating was observed. Electrolytes containing [TFSI]− anions showed superior stability compared to those with [FSI]− anions in battery tests.