• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.494-495
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• 2011

초고용량의 커패시터는 신재생 에너지 이용의 증가와 더불어 이용 영역이 점차 넓어지고 있어 유망신규시장의 창출이 기대된다. 따라서, 슈퍼커패시터의 성능을 측정하여 시험할 수 있는 충방전 순환 시험기가 필수적이라 할 수 있다. 이를 위해 슈퍼커패시터의 기본 충/방전 특성을 기준으로, 충전과 방전시의 고속계측이 가능하도록 용량 및 내부저항 측정을 위한 회로와 전압유지특성을 측정하기 위한 회로를 설계하였다. 5V, 100A Proto-type의 충방전 시험 시스템 구축으로 특성 평가결과, 전압 및 전류 측정 정밀도 ${\pm}$ 0.1%이내로 확인하였고, 데이터 모니터링 및 로깅을 위한 프로그램을 제작하였다. 또한 전체시스템 구성과 실험결과를 통해, 본 연구에서 개발하고자 하는 슈퍼커패시터용 충방전 시험 시스템이 실제 응용 가능함을 확인하였다.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.236-237
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• 2011

고유가 시대의 도래와 화석연료의 소비를 줄일 수 있는 환경 친화적 자동차인 하이브리드 자동차의 도입이 일본, 미국 등을 중심으로 꾸준히 증가하고 있다. 이 중 마일드 하이브리드 시스템은 Idle Stop-Start, Launch Assist 및 회생 제동 등의 기능을 적용하여 연비개선의 효과를 갖고 있다. 본 논문에서는 기존 화석 연료를 사용하는 자동차에도 적용이 가능하며 2차 전지에 비해 수명이 긴 슈퍼 커패시터를 사용하여 MHEV용 5kW급 저압 인버터 시스템을 개발하였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.901_902
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• 2009

This paper describes the development of a three-phase Line-Interactive DVR(Dynamic Voltage Restorer), which is applied to Hybrid detection method and super-capacitor. The operational feasibility was verified through computer simulations with PSCAD/EMTDC software, and experimental will be work with 3kVA prototype. The developed system can compensates the input voltage sag and interruption within 2ms, in which the maximum allowable sensitive load, such as computer, communication equipment, automation equipment, and medical equipment. The developed system has a simple structure to be easily implemented with commercially available components and to be highly reliable in operation.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.730-734
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• 2007

National projects on renewable energy and new energy are driven more actively than ever in many countries for the exhaustion of fossil fuel energy from the turn of the century. Such activities began to spread out in railway industry with centering around west European countries. Electric energy is generated on the hybrid vehicle itself, which contributes to reduction of the cost for construction of the infrastructure required for the supply of electric power. Hybrid tram is mainly composed of propulsion system to control electric energy, automatic guidance system to control steering and operation, and central vehicle unit to control and monitor major electronic devices. Generation and supply of electric power are made by the combination of engine generator and battery, or fuel cell and super capacitor.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.514-520
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• 2010

This paper is about control algorithms that bi-direction DC-DC Converter using Super Capacitor and regenerative power from DC feeding system in train. In order to take advantage of regenerative energy efficient, charge and discharge level value of energy storage system serve as an important factor. Respect to output fluctuations of the substation and catenary voltage changing, we offers Charge-Discharge Auto Level Tuning Algorithms to improve system following of Energy Storage System.

• Carbon letters
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• v.15 no.2
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• pp.146-150
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• 2014

In this work, activated carbon nanofiber (ACNF) electrodes with high double-layer capacitance and good rate capability were prepared from polyacrylonitrile nanofibers by optimizing the carbonization temperature prior to $H_2O$ activation. The morphology of the ACNFs was observed by scanning electron microscopy. The elemental composition was determined by analysis of X-ray photoelectron spectroscopy. $N_2$-adsorption-isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller and Dubinin-Radushkevich equations. ACNFs processed at different carbonization temperatures were applied as electrodes for electrical double-layer capacitors. The experimental results showed that the surface morphology of the CNFs was not significantly changed after the carbonization process, although their diameters gradually decreased with increasing carbonization temperature. It was found that the carbon content in the CNFs could easily be tailored by controlling the carbonization temperature. The specific capacitance of the prepared ACNFs was enhanced by increasing the carbonization temperature.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.1
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• pp.51-56
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• 1984

This paper describes the analysis and design of a GaAs FET distributed amplifier connecting a series capacitor to get a super wide bandwidth by reducing the gate line attenuation constant. In this approach a design example with a 300$\mu$ gate length FET devices is presented, and the abtained results are; that without series capacitors the bandwidth is 2-12 GHz, but with capacitors 2-20 GHz in flat gain.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.323-326
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• 2006

This paper shows the comparison of operating characteristics between squirrel cage induction generator and DFIG(Double Fed Induction Generator). Because squirrel cage induction generator consume the reactive power due to magnetizing reactance, the capacitor is need to compensate the reactive power. Otherwise, two back-to-back PWM voltage-fed inverters connected between the stator and the rotor allow sub/super synchronous operation with low distortion currents. In this paper, the response characteristics of squirrel cage induction generator and DFIG, were analyzed and investigated using PSCAD/EMTDC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.130-131
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• 2005

In the era of submicron devices, super ultra thin gate oxide characteristics are required. Titanium silicide process has studied gate oxide reliability and dielectric strength characteristics as the composition of gate electrode. In this study the author observed process characteristics on MOS structure. In view point of the process characteristics of MOS capacitor, the oxygen & Ti, Si2 was analyzed by SIMS analysis on before and after annealing with 1,2 step silicidation, the Ti contents[Count/sec]of $9.5{\times}1018$ & $6.5{\times}1018$ on before and after 2'nd anneal. The oxygen contents[Count/sec] of $4.3{\times}104$ & $3.65{\times}104$, the Si contents[Count/sec] of $4.2{\times}104$ & $3.7{\times}104$ on before and after 2'nd anneal. The rms value[A] was 4.98, & 4.03 on before and after 2'nd anneal.

• 전기의세계
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• v.46 no.4
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• pp.22-27
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• 1997

DRAM(Dynamic Randum Access Memory)은 반도체 소자 중 가장 대표적인 기억소자로, switch 역할을 하는 1개의 transistor와 data의 전하를 축적하는 1개의 capacitor로 구성된 단순한 구조와 고 집적화에 용이하다는 이점을 바탕으로, super-computer에서 가전제품, 통신기기 및 산업기기에 이르기까지 널리 이용되어 왔다. 한편으로 DRAM사업은 고가의 장치사업으로 조기 시장 진입을 위하여 초기에의 막대한 자본투자, 급속한 기술발전, 짧은 life cycle, 가격급락 등이 심하여, 시한내에 투자회수가 이루어져야 하는 위험도가 큰 기회사업이라는 양면성을 가지고 있다. 이러한 관점 때문에 새로운 DRAM 기술은 매 세대마다 끊임없이 빠른 속도로 개발되어왔다. 그러나 sub-half-micron 이하의 DRAM세대로 갈수록 그에 대한 새로운 기술은 점차 어렵게 되어가고, 한편으로는 system의 다양화에 따른 요구도 강하여, 이제는 통상적인 DRAM의 고집적화 및 저가의 전략만으로는 생존하기 어려운 실정이므로 개발전략도 수정하여야만 할 것이다. 이러한 어려운 기술한계를 극복하기 위하여 새로운 소자기술 및 공정개발에 애닿 breadthrough가 이루어져야 할 것이다. 이러한 관점에서 현재까지의 DRAM개발 추이와 향후의 기술방향에 관하여 몇 가지 중요한 item을 설정하여 논의하여 보기로 한다.