• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2162-2164
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• 1997

High Voltage High Current Pulsed Electric Fields (HVHC-PEF) is a promising technology for the non-thermal pasteurization of foods and a sound complement or replacement to traditional thermal pasteurization, which inactivates bacteria and other microorganisms harmful to humans, but also degrades color, flavor, texture and nutrients. Foods can be pasteurized with pulsed electric fields at ambient or refrigerated temperatures for a short treatment time of seconds or less and the fresh-like quality of food is preserved. Although successful in laboratory tests, applying HVHC-PEF to food pasteurization on a large scale presents many unresolved engineering problems. In this paper the design considerations for 25kV 1kA class HVHC-PEF pasteurization equipment are analyzed and experimental results are discussed.

• Transactions on Electrical and Electronic Materials
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• v.8 no.2
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• pp.97-102
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• 2007

The charging/discharging characteristics of electric double layer capacitors (EDLCs) for an electric power storage device application were investigated. The specific area of the carbonaceous electrode surface by the BET method was in the range of $1800{\sim}2000\;m^2/g$. The charge distributions during charging and discharging were measured by means of a pulsed-electro-acoustic (PEA) method, and the voltage characteristics of EDLCs connected to solar cells were evaluated. The results showed that the distributions of positive and negative charges were spatially uneven, which was due to the mobility of the positive and negative charges in the carbonaceous electrode surface of the EDLCs. The charge accumulation region concentrated on central part of the carbonaceous electrode and the required times for charging and discharging were almost same.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.266-268
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• 1997

High Voltage High Current Pulsed Electric Fields (HVHC-PEF) is a promising technology for the non-thermal pasteurization of foods and a sound complement or replacement to traditional thermal pasteurization, which inactivates bacteria and other microorganisms harmful to humans, but also degrades color, flavor, texture and nutrients. Foods can be pasteurized with pulsed electric fields at ambient or refrigerated temperatures for a short treatment time of seconds or less and the fresh-like quality of food is preserved. Although successful is laboratory tests, applying HVHC-PEF to food pasteurization on a large scale presents many unresolved engineering problems. In this paper the design considerations for 25kV 1kA class HVHC-PEF pasteurization equipment are anlyzed and experimental results are discussed.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1661-1663
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• 2001

This paper describes the dielectric characteristics of composite dielectric film for pulsed power capacitors. The relative electric permittivity(${\varepsilon}'$) and the dielectric dissipation factor(tan$\delta$) were measured for polypropylene (PP) membranes, kraft paper for capacitors(CP) and composite dielectric films(PP+CP), respectively, in a frequency range of $1{\sim}10^4$[Hz], and in temperatures ranging from -50[$^{\circ}C$] to 110[$^{\circ}C$]. As a result, the variation of the electric permittivity was observed similarly for PP and CP. Dielectric dispersion was observed in frequency domain in PP, CP and composite dielectric films.

• Korean Journal of Agricultural Science
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• v.40 no.1
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• pp.13-18
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• 2013

Effect of electric pulse stimulation was tested on the fruit body formation of valuable mushroom Tricholoma matsutake in the field of natural habitat of this mushroom. After applying the electric stimulator to the specific area of pine forest we found that the treatment especially stimulated the fructification of T. matsutake. And the most valuable findings of our study was that only our treatment plots showed fruit body formation whereas the control plots and the whole natural habitats of our study area showed zero production of this mushroom during the same time. From the point of view of mushroom production, our experiment shows that fruit body production can be upgraded by using pulsed power as an electrical stimulation in the field of the natural habitat of this mushroom. These findings from our experiment confirm the effectiveness of the significance of pulsed power technology for the improvement of T. matsutake fruit body production in the natural habit of this mushroom.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.119.1-119.1
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• 2014

Toxic waste disposal: Many people think that when toxic waste is dumped into the ocean or into the air, it disappears. This belief is incorrect. Rather than disappearing, it accumulates over time and slowly destroys the environment. Ultimately, it leads to the destruction of human race. Plasma is environmentally friendly: Plasma is environmentally friendly because it is created and disappears. When plasma is formed on the earth, you need certain conditions such as accelerating electrons by an electrical discharge or a particle accelerator. When this is gone, plasma completely disappears, leaving no impact on the environment. Plasmas produce radicals: Even if plasma density is low at atmospheric pressure, many radicals (excited states of molecules) are created. These radicals are chemically very aggressive. So instead of using harmful chemicals, plasma can be utilized for less of an impact on the environment. Plasma can reach very high temperatures: Plasma is also useful because when you control the density, you can easily reach high temperatures up to $5000{\sim}6000^{\circ}C$ at atmosphere pressure. Because of this heat and the chemical aggressiveness of the plasma, there are many green applications for plasma technology. Pulsed power technology: Pulsed electric field for extraction, drying and killing bacteria. Treatment of biological tissue by pulsed electric fields: Extraction of substances from cells: Sterilisation, Medical applications, Growth stimulation, Food preparation. Each application has its specialities, especially with respect to pulse shape and electric field strength.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.121-121
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• 2010

As the industrial technology is getting higher, the pulsed power technology is required from various fields such as thermonuclear fusion energy sources, military applications, electric power distribution, and a variety of new specialized needs. This technology deals with the generation of very high power electromagnetic pulses through fast switching. We fabricated a pulsed power generator, named EMD pulse generator, by using Marx circuit with 200 kV high, 50 ns fast rise time. In this paper, we described about an effect of stray capacitance of coaxial Marx generator, EPG-AM200k, and a comparing the results of experiments and circuit analysis.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.4
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• pp.322-332
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• 2022

Energy storage capacitors based on dielectric ceramics with superior polarization properties and dielectric constant can provide much higher output power density due to their very fast energy charging/discharging rates, which are particularly suitable for operating pulsed-power devices. For an outstanding energy storage performance of dielectric capacitor, a large recoverable energy density could be derived by introducing a slim polarization-electric field hysteresis loop into dielectric materials by various technical approaches. Many research teams have explored various dielectric capacitor technologies to demonstrate high output power density and ultrafast charging/discharging behavior. This article reviews the recent research progress in high-performance dielectric capacitors for pulsed-power electronic applications.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1347-1349
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• 1995

Insulators contaminated by salt particles may cause flashovers in humid climate or light rain. Therefore, the quantity of salt on insulators should be monitored not to exceed a critical value. We propose a new remote sensing technique to measure the quantity of salt on insulators of power systems. The amount of the salt is measured from the intensity of the spontaneous emission from the sodium atoms. In this paper, a compact remote on-line salt-meter composed of Q Switch pulsed Nd:YAG laser and emission signal detection system will be introduced. And as the first result of this study, the operating characteristics of our developing laser system is also introduced.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.147-148
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• 2006

Sl-Thyristor는 기존의 Power semlconductor인 단일 IGBT,MOSFET과 비교하여 높은 정격 전압과 대전류의 소호가 가능하며 빠른 turn on swithcing time을 가지는 특성이 있다. 하지만 게이트 드라이버를 이용한 Sl-Thyristor의 turn on 구동시에는 전압구동의 특성과 turn 0ff시에는 전류 구동의 특성에 가까운 구동 특성이 요구되기 때문에 스위칭 요구 특성에 맞는 게이트 드라이버의 설계 및 제어가 쉽지 않다. 본 논문은 펄스 파워 어플리케이션으로 Sl-Thyristor(PT-201 5kV/100A)를 사용하여 pulsed power moduiator용 Sl-Thyristor의 게이트 드라이버의 요구인 빠른 turn on switching 특성과 turn off 시 Si-Thyristor 내의 전하를 빨리 제거하기 위한 조건을 제시하고 있다.