• Title/Summary/Keyword: charge-discharge

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The Fundamental Study About Partial Discharge Detection With The Radiated Electromagnetic Wave Characteristics (방사전자파 특성을 이용한 부분방전 검출의 기초연구)

  • Lee, Sang-Hun;Park, Gwang-Seo;Kim, Chung-Nyeon;Lee, Hyeon-Dong;Song, Hyeon-Jik;Kim, Gi-Chae;Lee, Gwang-Sik;Lee, Dong-In
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.49 no.7
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    • pp.412-417
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    • 2000
  • This paper offer fundamental materials about Partial Discharge(PD) detection by electromagnetic waves. All spectrum data-usually used as grape- can be used as numbers. And then the average of background noise spectrum strength was made. Average value subtract from every data. Then average value appeared, graphed. The graph was compared with the magnitude of charge. The shape of changes is similar, and the change of electric field strength could be seen in one sight. When the magnitude of charge is over than 100[pC], antenna can detect partial discharge. So this method will be very useful to diagnosis of insulation. It the performance of the antenna used in this experiment is analyzed, good results can be obtained.

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A Study on the Impedance Characteristics and Mechanisms of Li Intecalation on the Tin Oxide-flyash Composite Electrodes (Tin Oxide-flyash Composite 전극의 리튬 이온 Intercalation 메카니즘과 임피던스 특성에 관한 연구)

  • Gu, Hal-Bon;Kim, Jong-Uk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.11
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    • pp.1224-1229
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    • 2004
  • The purpose of this study is to research and develop tin oxide-flyash composite for lithium Ion polymer battery. Tin oxide is one of the promising material as a electrode active material for lithium Ion polymer battery (LIPB). Tin-based oxides have theoretical volumetric and gravimetric capacities that are four and two times that of carbon, respectively. We investigated cyclic voltammetry, AC impedance and charge/discharge cycling of SnO$_2$-flyash/SPE/Li cells. The first discharge capacity of SnO$_2$-flyash composite anode was 639 mAh/g. The discharge capacity of SnO$_2$-flyash composite anode was 563 and 472 mAh/g at 6th and 15th cycle, respectively. The SnO$_2$-flyash composite anode with PVDF-PMMA-PC-EC-LiClO$_4$ electrolyte showed good capacity with cycling.

A study of the Improvement for Jitter and Discharge Delay Time in AC-PDP (AC-PDP에서 지터와 방전 늦음 시간 개선을 위한 연구)

  • Kwon, Shi-Ok;Kim, Ji-Sun;Joung, Bong-Kyu;Hwang, Ho-Jung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.506-507
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    • 2005
  • The effects of addition of $D_2$ to conventional gases [Ne-Xe and He-Ne-Xe] on the discharge characteristics were investigated in this work with the aim of improving the voltage margin, the wall charge and the jitter. The addition of an extremely small gas-inlet amounts of $D_2$ increased the number of electrons which improves. the $Xe^*$ density and $Xe_2^*$ density. As a result, the voltage margin, the jitter and the wall charge increased.

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Charge/Discharge Characteristics Analysis of Li-Polymer battery (리튬 폴리머 전지의 충방전 특성해석)

  • 최해룡;강병희;목형수;최규하;신우석
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.222-225
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    • 1999
  • Started upon it discovery by Wright et al in 1973, studies on the solid polymer electrolyte are being carried out vigorously. So, models of Li-polymer battery have been developed through R-L-C components combination and P-spice functional block in this paper. The impedance characteristics of Li-polymer battery with R-L-C components are presented. Simulation results using P-spice functional model are compared with measured charge/discharge characteristics.

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Decision of the Margin of the Sustain Voltage Based on the Wall-Charge Distribution (AC PDP의 벽전하 분포를 이용한 유지 펄스의 전압 마진 결정)

  • 하영석;권오경
    • Proceedings of the IEEK Conference
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    • 2000.06e
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    • pp.77-80
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    • 2000
  • This paper describes a new method to decide the margin for the sustain voltage of AC PDPs based on the wall-charge distribution. We model the discharge cell and measure the wall-charge when sustain pulses are applied to the AC PDP. The measured wall-charge distribution informs us of the voltage forming the maximum wall-charge which should be chosen as the sustain voltage.

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A Study on the Electrochemical Properties of Carbon Nanotube Anodes Using a Gradual Increasing State of Charge Method

  • Doh, Chil-Hoon;Park, Cheol-Wan;Jin, Bong-Soo;Moon, Seong-In;Yun, Mun-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.1
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    • pp.21-25
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    • 2004
  • From the gradual increasing state of charge (GISOC) observations, electrochemical behavior of multi-walled carbon nanotube│(lM LiP $F_{6}$ , EC,DEC,DME 3:5:5 volume ratio)│lithium cells was evaluated using the galvanostatic charge-discharge process. A MWCNT delivers a specific charge capacity of 1,300 mAh/g in a Li cell when cycled up to an end voltage of 0 V (vs. Li/L $i^{+}$ )at a constant current rate every 10 hours. However, in the present study, the specific discharge capacity obtained is 338 mAh/g, thus amounting to a coulombic efficiency of only 26%. Further, when the MWCNT│Li cells were tested using the GISOC method, two distinguishable linear-fit ranges were observed due to the intercalation/deintercalation of lithium, which were found to have II $E_1$, IIC $s_1$ and II $E_2$of 27.3%, 372 mAh/g, and 25.5%, respectively. Q $c_1$, could be calculated from the data of IIE and IICs of each range by the modified equation "II $C_{sum}$= $\Sigma$( $Q_{C}$- $Q_{D}$)=(II $E_{1}$$^{-1}$ ) $Q_{Dl}$ +(II $E_2$$^{-1}$ -1) ( $Q_{D2}$- $Q_{Dl}$ ) + IIC $s_1$= $Q_{Cl}$ - $Q_{Dl}$ ". Results of the GISOC method could be converted to the results of galvanostatic charge-discharge process, irrespective of the state of charge of the cell or battery.ery.y.y.

Partial Discharge Data Analysis with Unsupervised Classification (무감독분류 기법에 의한 부분방전 데이터 분석)

  • Cho, Kyungsoon;Hong, Seonhack
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.14 no.4
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    • pp.9-16
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    • 2018
  • This study described partial discharge(PD) distribution analysis between the XLPE(Cross-Linked PolyEthylene)and EPDM(Ethylene Propylene Diene Monomer) interface with unsupervised classification. The ${\phi}-q-n$ patterns were analyzed using phase resolved partial discharge(PRPD). K-means cluster analysis forms a cluster based on similarities and distances among scattered individuals, and analyzes the characteristics of the formed clusters, dividing the multivariate data into several groups according to the similarity of each characteristic, Is a statistical analysis that makes it easier to navigate. It was confirmed that the phase angle of the cluster with the maximum discharge charge was concentrated around $0^{\circ}$ and $180^{\circ}$ at 30 kV after the initial phase distribution localized around $90^{\circ}$ and $300^{\circ}$ expanded to the whole phase angle according to the voltage rise. The Euclidean distance between the center of gravity and the discharge charge in the ${\Phi}-q$ cluster increased with increasing applied voltage.

The Electrochemical Characterization of $LiMn_{2-y}M_{y}O_{4}$ Cathode Material. III. The Effect of Temperature on the Charge-discharge Property and AC Impedance of $LiMn_{2-y}M_{y}O_{4}$ ($LiMn_{2-y}M_{y}O_{4}$ 정극 활물질의 전기화학적 특성. III. $LiMn_{2-y}M_{y}O_{4}$의 충방전 특성과 AC 임피던스의 온도 의존성)

  • 정인성;구할본;김종욱;손명모;이헌수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.14 no.8
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    • pp.663-669
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    • 2001
  • Spinel LiM $n_2$ $O_4$ and LiM $n_{1.9}$M $g_{0.1}$ $O_4$ power was synthesized with solid-state method by calcining the mixture of LiOH.$H_2O$, Mn $O_2$ and MgO at 80$0^{\circ}C$ for 36 h in an air atmosphere. To investigate the effect of temperature on he cycle performance of cathode material during cycling, charge-discharge experiments and ac impedance measurement were performed. Initial discharge capacity was gradually increased with the increase of charge-discharge temperature. Discharge capacity at high temperature was suddenly decreased during cycling. On the other hand, discharge capacity at low temperature was almost constant during cycling. It confirmed that Mn dissolution is serious at high temperature than at low temperature. LiM $n_2$ $O_4$ and LiM $n_{1.9}$M $g_{0.1}$ $O_4$ showed the best capacity and stability at room temperature.ure.ure.

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Silent Disicharge Characteristics of Alumina Discharge Tube for Ozone Generation (오존발생을 위한 알루미나 방전관의 무성방전특성)

  • 김학규;곽동주
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.783-786
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    • 2001
  • Recently deep interests and attractions have been paid on the generation of ozone, which is widely used to remove bad smell and to clear water. Silent discharge is considered as one of the most effective methods to generator ozone. In this paper, silent discharge reactors were made, waich were filled with different dielectric materials, and some silent discharge charactistics were investigated experimantaiiy.

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AC PDP(Plasma Display Panel)의 방전 특성 해석

  • 황기웅;정희섭;서정현
    • Proceedings of the Korean Vacuum Society Conference
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    • 1997.07a
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    • pp.173-176
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    • 1997
  • A numerical analysis of the micro-discharge in an AC pplasma dispplay cell has been made using time-deppendent, 2-dimensional multi-fluid equations to understand the discharge pphysics of He-Xe discharge. The time deppendent distribution of the electron tempperature, densities of electrons, various ions and excited sppecies, and the effects fo the wall charge accumulated on the dielectric surface are obtained and comppared with the results of direct observation of time deppendent behavior of VUV and visible sppectra from single discharge cell observed using a gated, image intensified CCD to elucidate the discharge physics.

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