• Title/Summary/Keyword: electric charges

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The Effect of Additive on the Electric conductivity of Insulating Oil (절연유의 전기전도에 미치는 첨가제의 영향(II))

  • Chung, K.H.;Kim, Y.B.;Kim, Y.I.;Park, S.H.;Park, J.Y.;Lee, D.C.
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1630-1632
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    • 1996
  • The static charges are generated by streaming electrification phenomena when insulating oil flowing by force for the purpose of cooling at the internal of Ultra-high power transformer. In this thesis, their elimination method was studied. In this paper the effect of Additive on the electric conductivity of Insulating oil is studied. The variation of electric conductivity disappear when Additive is molten in insulating oil, the variation of Additive is not enough to decrease streaming electrification of insulating oil(${\sigma}>10^{-12}$[S/cm]).

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A Study on 3 Dimensional Electric Field Analysis of the Finite Transmission Line (유한장 선로의 3차원 전계 해석에 관한 연구)

  • Lee, Byeong-Yoon;Myung, Sung-Ho;Min, Suk-Won;Kim, Eung-Sik;Park, Jong-Keun
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1565-1567
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    • 1994
  • This paper describes a methodology for the three dimensional electric field calculation around parallel and orthogonal transmission lines. A nonuniform modeling method of finite line using linear line charges is proposed through the error analysis, Several examples of three dimensional electric field calculation are carried out by this method.

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The Analysis on the Deformation of Electrostrictive Polymer Film with respect to Time under Constant Voltage

  • Park, Kyung-Chul;Yun, Ji-Won;Jeon, Jae-Wook;Park, Hyoukryueol;Kim, Hunmo;Nam, Jae-Do
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.46.5-46
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    • 2001
  • Electrostrictive polymer is deformed by electric force generated by electric field built by high voltage. When high voltage is applied to the electrostrictive polymer film in which the electrodes such as conductive grease or carbon powder are installed, it expands in the direction of area. Because electrostrictive polymer is incompressible and electric force is applied to it in the direction of thickness. Electrostrictive polymer film in which electrodes are installed, functions as a parallel-plate capacitor. Therefore anode and cathode charges are piled up or both electrodes and there exists attractive force that functions as pressure in the direction of thickness. So the thickness of electrostrictive polymer becomes thicker ...

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Pre-Charged Particle Deposition in an Impactor subjected to an Electric Field (전기장이 형성된 관성 충돌기에서 대전 입자의 거동과 부착 특성에 대한 연구)

  • Park, Hyung-Ho;Kim, Sang-Soo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.3
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    • pp.299-310
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    • 1999
  • Effect of electrostatic and inertial forces on the pre-charged particle deposition was theoretically and experimentally studied by introducing the inertia impactor subjected to an electric field. To derive the analytic solution, we assumed that a flow was an ideal stagnation flow, a particle had saturation charges, and the electric field within the test section was uniform. On the other hand, $Al_2O_3$ particle groups were used as the test particles, which mean sizes were $1{\mu}m$, $3{\mu}m$, and $5{\mu}m$. To measure the deposition efficiency, the light scattering method was used. The results showed that the deposition efficiency was minimized at a certain nozzle velocity as increasing the nozzle velocity, only if the electric force was applied. As the electric field strength increased, $Stk_{50}{^{1/2}}$ was decreased, and its decreasing rate was reduced with increasing the flow velocity. Moreover the existence of electric field was against the cut-off performance of the inertia impactor.

A STUDY ON THE CHARACTERISTICS OF DIELECTRIC LAYER ON THE DISCHARGE ELECTRODES IN AC PDP (AC PDP 유전층의 절연내력과 투명도에 관한 연구)

  • Lee, Sung-Hyun;Kim, Bang-Ju;Kim, Gyu-Seup;Park, Chung-Hoo;Cho, Jung-Soo
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1788-1790
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    • 1998
  • The dielectric layers in AC plasma display panel(AC PDP) are essential to the discharge cell structure, because they protect metal electrodes from sputtering by positive ion bombarding in discharge plasma and form a sheath of wall charges which are essential to memory function of AC PDP. This layer should have high dielectric strength and also be transparent because the luminance of PDP is strongly correlated this layer. In this paper, we discussed the dielectric strength and transparency of the dielectric layer under various conditions. As a result, on the $15{\mu}m$ thickness, the minimum dielectric strength was $29V/{\mu}m$ and the transmittance coefficient was about 80% after $570^{\circ}C$ firing process. It can be proposed that the resonable dielectric thickness in AC PDP is $15{\mu}m$ because it has about 80V margin on the maximum applied voltage.

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Triboelectrostatic Separation System for Separation of PVC and PS Materials Using Fluidized Bed Tribocharger

  • Lee, Jae-Keun;Shin, Jin-Hyouk;Hwang, Yoo-Jin
    • Journal of Mechanical Science and Technology
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    • v.16 no.10
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    • pp.1336-1345
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    • 2002
  • A triboelectrostatic separation system using a fluidized bed tribocharger for the removal of PVC material in the mixture of PVC/PS plastics is designed and evaluated as a function of electric field strength, air flow rate, and the mixing ratio of two-component mixed plastics. It consists of a fluidized-bed tribocharger, a separation chamber, a collection chamber and a controller. PVC and PS particles can be imparted negative and positive surface charges, respectively, due to the difference in the work function values of plastics suspended in the fluidized-bed tribocharger, and can be separated by passing them through an external electric field. Experimental results show that separation efficiency is strongly dependent on the electric Deld strength and particle mixing ratio. In the optimum conditions of 150 Ipm air flow rate and 2.6 kV/cm electric field strength a highly concentrated PVC (99.1%) can be recovered with a yield of more than 99.2% from the mixture of PVC and PS materials for a single stage of processing.

Electrical fire hazards in the domestic circuit protected by Electric Leakage circuit Breaker(ELB) (누전차단기가 설치된 옥내전로에서의 화재위험성)

  • 홍성호;김두현;김상철;김상렬
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 1998.11a
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    • pp.335-340
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    • 1998
  • This paper presents a study on the electrical fire hazards of leakage current in a distribution circuit simulating a domestic circuit for low voltage. In this simulated circuits, total charges and energy of leakage current are calculated by a theoretical approach and compared with the results obtained from experiments, The approach and results become a cornerstone for studying and analyzing causes of electrical fires.

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A Study on Application of Geothermal Heatpump System for Apartments (공동주택용 지열냉난방 적용성 검토 연구)

  • Baek, Sung-Kwon;Ahn, Hyung-Jun;Lee, Dong-Cheul;Im, Seung-Kyun
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.574-578
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    • 2009
  • Residential is the biggest market for geothermal heatpump systems in the world. However It could not be considered as a big market in Korea. Serious problems are hidden. In this paper, I will discuss about with other problems that we must solve.

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New Ramp-reset Waveform for Fast Addressing in AC-PDPs

  • Kim, Oe-Dong;Ahn, Byoung-Nam;Choi, Kwang-Yeol;Yoo, Eun-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07a
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    • pp.643-646
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    • 2005
  • We present new ramp-reset waveforms that realize fast addressing in AC-PDPs. These waveforms distort the distribution of wall charges on the surface of a phosphor layer: hence, the enhanced electric field helps to ignite a cell faster. They also reduce the black luminance: the divide of erasing ramp down discharges into two parts, i.e. a surface discharge and a vertical discharge, makes lower luminance.

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Surface Deterioration Phenomena in Polyethylene under Corona Discharge (Corona 방전에 의한 Polyethylene의 표면열화현상)

  • 성영권;송진수;민남기
    • 전기의세계
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    • v.24 no.5
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    • pp.82-90
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    • 1975
  • This study investigated the deterioration phenomena of the Polyethylene surface contaminated with organic(Saccharose) or inorganic(NaCl) matters through electrical and optical experiments. And also these experimental results relatively well coincided with which was treated by theoretical process. On the electrical experiment, relation between electric field intensity in corona discharge and time reached to the breakdown, and relation between total amount of charges discharged and increment of applied voltage were investigated. On the optical experiment, discharge time dependence of surface deterioration rate and process of surface deterioration in the X-ray diffraction pattern were investigated. It was concluded that chemical effects by the corona discharge deteriorated insulation characteristics of Polyethylene surface.

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