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An experimental study on dielectric response of the crosslinked polyolefin (XLPO) insulation of the unshielded cable under electric field and heat flux
(2021-05-19)
Singhasivanon, Jakawan
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Jirasuwankul, Nirudh
Nowadays, crosslinked polyolefin cables (XLPO cables) are more popular and more famous for electrical insulation. In order to study and analyze the characteristics of insulation. The polarization and depolarization of current measurements (PDC measurement) is one of the advance methods that can compute and provide dielectric reaction parameters. In this paper, aim to study dielectric response of the XLPO insulation of unshielded cables under electric fields and heat fluctuations by measuring permittivity (ϵ′, r), conductivity (σ) and dissipation factors (Tan δ). The experimental results indicate permittivity is rather constant at different field strengths and temperatures and are similarly to XLPE insulation. It is also found that the activation energy of XLPO insulation is 0.77 eV. Future more, action energy in this research can excite electrons or ions in valent band within insulations to change the state from non-conductivity to conductivity.
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Conductivity analysis of lubricant in terms of deterioration by using a hall effect sensor
(2019-11-01)
Sriratana, Witsarut
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Prommapit, Sombat
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Khwankityotha, Yannadech
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Sriratana, Lerdlekha
This paper investigates the efficiency of lubricant analysis by using electrical conductor theory that applied to check the performance of the lubricant, it will be indicate a life cycle of lubricant. The measurement process has led Electrochemical cell, Induction coil and Hall Effect sensor for electrochemical field analysis and compare it with electrical conductivity. In conductivity measurement experiment, we consider dynamic measurement velocity at 80 RPM with a lubricant Semi-Synthetic 10W-40 type by 5 different life cycle samples ratio, Used lubricant: Unused lubricant are 100% (4: 0), 75% (3:1), 50% (2:2), 25% (1:3) and 0% (0:4). The voltage output of Hall Effect sensor of 100% sample measurement at 100 degree Celsius is higher than the voltage output of 75%, 50%, 25% and 0% sample are 7.04%, 12.21%, 21.25% and 28.65%, respectively. The average percentage of Hall Effect sensor errors with the dynamic measurement method of the 5 lubricant samples was 2.87. Even though this measurement method had a high percentage of errors, but it has a cost advantage over the current measuring devices such as the Viscometer which is expensive cost.
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Development of a Ternary Composite of PU Resin/Carbon Black/PZT for Mechanical Energy Harvesting Application
(2018-01-01)
Punsawat, Woratat
;
Makcharoen, Worawut
Today, rapid depletion of energy sources forces us to discover alternative sustainable electrical energy sources quickly. The aim of this work was to develop a ternary composite of PU resin/carbon black/PZT to be an efficient mechanical energy harvester. Specifically, this present work attempted to find the optimum weight ratio of a PU resin/carbon black/PZT composite that could provide the highest mechanical-to-electrical conversion efficiency. The PU resin was the main matrix. Carbon black (CB) was added to improve conductivity while still maintaining good casting property. Then, PZT was added to generate electricity. Testing several weight ratios of this composite, it was found that the samples ratio of 60:20:20 was optimum and able to generate an average voltage of 0.357 V/in2. This ternary composite material has a candidate to into a practical and efficient electrical energy harvester source.
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Analysis of liquids conductivity using hall effect sensor based on electromagnetic field properties
(2017-11-10)
Sokjabok, Siwakon
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Sriratana, Witsarut
;
Satthamsakul, Sutham
This paper presents a new methodology of analyzing liquid conductivity via the Hall Effect sensor based on electrochemical properties. Two different magnetic field cores with the same coil length (10 m, AWG 31) were studied, namely ferrite solenoid cores and toroidal iron powder cores (T131-26). The magnetic field generated by both type of cores was then used to generate a Hall voltage with the cores ratios of 1 : 1. The output Hall voltage is, in turn, sent through a microcontroller, together with a 10 bit converter for real time data analysis. The magnetic-field density of the solenoid for analyzing the conductivity of brine is 31 mT for solenoid, and 10.74 mT for toroid cores, respectively. Results from other materials are compared to the reference conductivity values of salt solution, which amounts to 16.211 mS/cm when assessed with the solenoid core, and 16.406 mS/cm when assessed with the toroid core.
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New electrical shunt with two rectangular holes in a copper plate
(2015-11-01)
Kando, Masaaki
;
Pattanadech, Norasage
A new concept of an electrical shunt with two rectangular holes in a copper plate (ESRP) has been developed to be used for measuring a large current with a short-duration steep wave in a high-voltage field. The ratio of the input current to the output current is 10<sup>6</sup>, as obtained from a DC voltage test circuit. The electrical shunt has a special configuration. To verify the shunt current ratio of ESRP in a real application, the shunt current was connected to a sphere-to-sphere electrode breakdown test circuit with a 10 mm gap to measure the large damping current (8.4 kA) of a DC breakdown voltage. The voltage signal from the shunt was transmitted to excite two light-emitting diodes (max. 50 mA, 4 V), which were reverse-connected in series. The light-emitting diodes operated properly and were illuminated, which validated the capability of the newly designed electrical shunt.
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The study of wireless power transmission under water-to-air mode
(2015-10-01)
Khan-Ngern, Werachet
;
Zenkner, Heinz
This research proposes the preliminary study whether the power transmission is possible or not. The wireless power transmission using particular resonance technique with series resonance for transmission and parallel resonance for receiver has been proposed. The study is focused on the wireless power transmission on waterto- air mode on reversed osmosis water and various salt water concentrations. The transmitted power is up to 7 W at a frequency of 6.78 MHz across a distance in the range between 10 mm to 60 mm has been demonstrated. Finally, the effect of water type and the percentage of salt concentration on wireless power transmission attenuation are presented and analyzed.
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Permeability of fluid flow through a periodic array of cylinders
(2015-01-01)
Chamsri, Kannanut
;
Bennethum, Lynn S.
The three-dimensional model of an incompressible Newtonian viscous fluid slowly flowing through a periodic array of cylinders is considered. We use homogenization to determine a system of equations that are then solved numerically to calculate the permeability. We determine the permeability as a function of the angle the cylinders make with the bottom surface. Numerical results are obtained using a Taylor-Hood mixed finite element method. The numerical approach is validated by comparing the results with computed results of Rocha and Cruz, for a simple cubic array of spheres, with good agreement. Results are presented for different cylindrical densities and angles. When the flow aligns and is perpendicular to an array of cylinders, the results are validated with experimental data. The spherical part of the permeability is compared with the Kozeny-Carman equation. Applications of these results include modeling fluid flow through biological hairlike structures such as animal hair, glass rods, fiberglass, filter pads, polymer gel, collagen, nylon fibers and natural rice field or trees.
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Effects of tetramethylene sulfone solvent additives on conductivity of PEDOT:PSS film and performance of polymer photovoltaic cells
(2013-01-01)
Keawprajak, Anusit
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Koetniyom, Wantana
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Piyakulawat, Phimwipha
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Jiramitmongkon, Kanpitcha
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Pratontep, Sirapat
A solvent additive in PEDOT:PSS solution is one of many methods to improve the conductivity of the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films. We explore a new type of the solvent additive, namely tetramethylene sulfone (TMS), for the fabrication of the PEDOT:PSS conductive layer in the ITO/PEDOT:PSS/P3HT:PCBM/TiO<inf>x</inf>/Al polymer photovoltaic cells, in comparison to a more common dimethyl sulfoxide (DMSO) solvent additive. At optimal conditions, the TMS additive at 10 wt.% has been found to enhance the conductivity of pristine PEDOT:PSS films from 0.04 S/cm up to approximately 189 S/cm, compared with the highest conductivity for the case of the DMSO additive at 15 wt.% of 117 S/cm. Possible mechanisms of this conductivity enhancement, relating to the polymer conformation and the film morphology, have been investigated by Raman spectroscopy, X-ray diffraction, atomic force microscopy, and transmission electron microscopy. The performance of the polymer photovoltaic cells fabricated with the solvent additives PEDOT:PSS films follows a similar trend to the conductivity of the films as a function of the additive concentration. The additives mainly lead to greater short circuit current density (J<inf>sc</inf>) of the photovoltaic cells. The highest power conversion efficiency (PCE) of 2.24% of the device has been obtained with the 10 wt.% TMS additive of, compared to the PCE of 1.48% for the standard device without solvent additive. © 2012 Elsevier B.V. All rights reserved.

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