• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1489-1491
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• 2004

PD in air is accompanied by light, sound and electromagnetic wave. Light and sound can be prevented from blocking between PD sources and sensor but electromagnetic wave can be transferred to long distance without any interference an captured by antenna. This paper investigated the wideband antenna is appropriate for sensing Partial discharge in air. PD was generated from simulated PD source which consist of needle and flat electrode with small gap. Signals obtained from wideband antenna were diminished in both time and frequence region with the distance between PD source and antenna.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1189-1192
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• 2007

We propose new driving schemes, asymmetry and long gap mode, of PDP having auxiliary electrode between scan and common electrode. For the asymmetric modes, the auxiliary electrode located nearly center of the primary electrodes is connected to the scan of common electrode during all periods of reset, address and sustain. For the long gap mode, it is electrically disconnected or maintained at dc voltage of Vs/2 during sustain period except the first several sustain pulses. The proposed structure and driving method can provide higher luminous efficacy by minimizing consumption energy. The effectiveness of the new driving schemes has been investigated for various Xe partial pressure conditions.

• Journal of Power Electronics
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• 제9권2호
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• pp.164-172
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• 2009

Recently, 2-dimensional flat light sources have been attracting much attention for its use in LCD backlight applications because of its high luminous efficiency and uniformity. A long-gap discharge, mercury-tree flat fluorescent lamp has been developed, which shows a high brightness ($>5000\;cd/m^2$) and high luminous efficacy (60 lm/W). Additionally, it has a wide operating margin and stable driving condition with the aid of an auxiliary electrode. For driving the lamp, a narrow pulse power to maintain the glow discharge state is required. Since there has been no research for this kind of lamp driving, this paper proposes a newly developed short-pulse, high-voltage lamp-driving scheme. The proposed lamp system uses a ballast with a coupled-inductor in order to raise the short pulse voltage up to the lamp ignition level and to obtain energy-recovery action during the glow discharge mode. The operation principles are presented and also the system performances such as the lighting efficiency, spatial and angular uniformities are evaluated by hardware experiments. The results show that the proposed lighting system is a good candidate for the next-generation of LCD backlight systems.

• 전기학회논문지
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• 제65권9호
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• pp.1571-1576
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• 2016

A Tesla coil is an electrical resonant transformer circuit invented by Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla coil can generate a long streamer with several million volts of electricity as a high voltage device. It is basically consists of a voltage transformer, high voltage capacitor, spark gap, primary coil, secondary coil and toroid. It is difficult to appear in the output size of the streamer is controlled by the spark gap. The general decision method of the length of streamer is to display the electric output in accordance with the design specifications in initial development plan. Design specifications and the electric output is determined by the application of facilities. In this paper the spark gap is replaced with periodic switching semiconductor device to control output voltage easily in order to apply overvoltage protective circuit due to a secondary coil and a performance test. In these days, their main use is for entertainment and educational displays of the museum, although small coils are still used as leak detectors for high vacuum systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1360_1361
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• 2009

일반적으로 AC PDP는 Xe+Ne이 동작가스로 사용된다. 본 연구에서는 Xe 분압을 50, 60, 80, 100 Torr로 고정한 상태에서 전체 가스압력을 변화시키고 Short 방전 갭으로 $80{\mu}m$를, Long 방전 갭으로 $180{\mu}m$ 적용함으로써 나타나는 AC-PDP의 방전특성을 분석하였다. 여기에 Xe 분압을 Short 방전 갭에서는 80, 100 Torr로, Long 방전 갭에서는 50, 60, 80 Torr로 각각 고정하고, Ne 압력을 변화시킴에 따라 나타나는 방전개시전압, 소비전력, 휘도, 발광효율을 측정하여 높은 휘도와 효율을 가지면서 방전개시전압을 최대한 낮출 수 있는 적정 조합을 연구하였다. 실험결과, Short 방전 갭 패널은 소비전력이 26% 낮았고, Long 방전 갭 패널은 휘도가 45% 높았다. 휘도, 소비전력 등 여러 가지 측면을 고려하였을 때, 방전개시전압이 가장 낮은 Short 방전 갭, Xe 절대분압 80 Torr, Xe 35%(Xe+Ne=286 Torr)에서의 방전 특성이 가장 우수하였다.

• 한국해양학회지:바다
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• 제8권2호
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• pp.138-150
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• 2003

만경강과 동진강이 담수를 유출하는 서해중부 연안에서 41,000 ha의 하구 천해역을 간척하기 위해 33 km의 새만금 방조제가 건설되고 있다. 이 연안역에 담수의 주 공급원은 방조제 북쪽에 위치하는 금강이다 현재 고군산군도 와 연결되고 있는 방조제는 이 해역을 세 지역으로 나누는데 방조제의 북서, 남서 그리고 동부(새만금) 지역이고, 새만금 지역 해수는 북방조제에 한 곳과 남방조제에 두 곳인 미축조 구간을 통해 교환된다. 이 연안역에서 저염수와 관련된 하계순환을 진단하기 위해 1998년과 1999년에 수온과 염분의 분포와 구조를 관측하였다. 북방조제 외측지역의 표층에서는 저염수의 혀모양 분포가 관측되었는데, 금강하구 입구에서 북서쪽으로 60 km까지 확장하고 외해수와 경계지어지는 강한 풀룸전선을 형성한다. 새만금 방조제 내측에서 염분분포는 두 강물이 병합되고 있으며 저염수가 북방조제 미축조 구간쪽으로 편향되었음을 보여준다. 남방조제 외측지역 표층에서는 곰소만으로부터 북쪽으로 확장하는 다른 저염수의 작은 혀모양 분포가 관측되었다. 이러한 저염수 분포와 전선구조 분석을 바탕으로 새만금 방조제 주변에 반시계방향의 연안수 순환을 제시할 수 있는데, 이는 방조제 내측에서 북방조제 미축조 구간으로 유출되는 하구 수와 남쪽 방조제 미축조 구간을 통하여 외해에서 유입하는 해수로 구성된다. 하지만 방조제 축조가 완성된 후에는 만경강과 동진강 담수 유출이 인위적이고 직접적으로 남방조제 외측으로 변경되기 때문에 방조제 주변 연안역 순환형태는 변화될 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1433_1434
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• 2009

AC PDP는 다른 디스플레이들에 비해 높은 소비전력과 낮은 발광효율에 대한 문제를 가지고 있다. 이러한 문제를 해결하기 위해 본 연구에서는 기존의 Stripe shape ITO(Indium Tin Oxide)전극구조에서 Lock shape ITO전극구조를 제안하였다. 이 구조는 long gap을 가진 Square형태의 전극구조에 'ㄱ'형태의 점화전극을 추가한 구조로, 소비전력을 줄이기 위해 전극면적을 줄이고, discharge current를 제어 하였다. 또한 점화전극 구조에 의해 늘어난 gap으로 인한 방전개시전압 상승을 줄 일수 있었다. 실험은 Stripe shape ITO구조와 Lock shape ITO의 전극구조들로 구성되어 있는 Test Panel을 직접 제작하여 방전개시전압, 휘도, 소비전력, 발광효율을 측정하여 그 특성들을 비교하였다. 그 결과 제안된 전극구조에서의 소비전력은 reference 구조에 비해 최대 18% 감소하였고, 발광효율은 최대 13% 상승을 함을 보였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권9호
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• pp.430-435
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• 2002

The $SF_{6}$ gas insulated power equipments have the insulation systems which are composed of $SF_{6}$ gas and insulation paper. It is repored that their insulation abilities are influenced by the $SF_{6}$ gas gaps in those insulation systems and gas pressures. This paper describes partial discharge phenomena with $SF_{6}$ gas pressures in insulation system of $SF_{6}$ gas-insulation paper Specimens of $SF_{6}$ gas-insulation paper were prepared and aramid paper was used as insulation paper. Partial discharge inception voltages(PDIV) and breakdown voltages for the existence of $SF_{6}$ gas gaps were measured by short term tests with gas pressures. Also, average PD quantities and pulse counts, life times of each specimens were calculated from the results of long term aging tests with gas pressures. It was found that the $SF_{6}$ gas gaps decrease increasing rates of PDIV and brealdown voltages according to gas pressure increase and the insulation breakdown caused by the smaller PD quantities than 1[pC] at the high gas pressure of 300kPa is due to the increase of energy density with increase of gas pressure.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.29-32
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• 2007

We analyzed the effect of cell resolution on the luminous efficacy through three-dimensional numerical simulation to understand the inherent discharge mechanism change in the plasma display panel. As the resolution increases from VGA to Full HD, the luminous efficacy decreases. With higher Xe content, VUV generation efficacy of Full HD becomes much lower than those of VGA or XGA cells, due to the increased plasma loss and lower electron heating. However a long electrode gap $140{\mu}m$ in Full HD cell with Ne-Xe [20%] results in the high luminous efficacy comparable to that of the XGA cell with $60{\mu}m$ gap. When comparing the effects of Xe content variation on the luminous efficacy of two different subpixel types, i. e., SDE (Segmented electrode in Delta color arrayed, Enclosed subpixel) [1] and conventional stripe barrier type in the XGA and Full HD cells, the luminous efficacy of SDE structure shows higher improvement in Full HD resolution compared with that of conventional type XGA cell, whose cause is identified as the reduced plasma loss.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.51-54
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• 2004

We have developed a new PDP cell structure called MARI(${\underline{M}}ulti$ ${\underline{A}}node$ for ${\underline{R}}eduction$ of ${\underline{I}}onic$ effect) and new driving scheme achieving a high luminous efficacy. The MARI PDP has middle electrode inserted between X and Y main electrodes. In the MARI PDP, reset and scan voltage is applied to middle electrode and sustain voltage is applied to X and Y electrode. Using a long gap sustain discharge we accomplished a high luminous efficacy. And we developed 42”full panel adopting MARI structure and new driving scheme and attained luminous efficacy of 2.35lm/W.