• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권4호
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• pp.253-260
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• 1999

In this paper, the impedance characteristic of wire-plate pulsed plasma reactor was investigated by experiment. The experiment have carried out under the several conditions of voltage, wire length and wire-plate distance. The impedance of reactor wad decreased with increasing voltage and wire length. The nature of discharge in reactor was changed from streamer corona to spark with increasing incident energy, from which we understood the critical energy density between the two discharges. Fromthis experiment, we proposed the method for the impedance matching between pulse generator and pulsed plasma reactor. Additionally, we succeeded in the analysis ofstray inductance of 0.5MW reactor using EMTP (ElectroMagnetic Transients Program). This means that EMTP is also useful for the analysis of inevitable stray inductance of forthcoming a large scale reactor.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권12호
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• pp.624-630
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• 2001

The trend of the regulations on environmental issues are getting tight. Responding to this trend new technologies such as moving electrodes, wide pitch and pulsed power supply are also introduced in the electrostatic precipitator(EP) systems. The introduction of wide pitch and moving electrodes enhances the system performance of the EPs by improving air-flow and by improving the ash reentrainment on rapping. The power supplies for the EPs developed up to date include thyristor-based dc or intermittent type, SMPS(switching mode power supply) type and the pulsed-power supply type. The use of the pulsed ones is known to improve dust-collecting efficiency of high resistivity ash and reduces back corona occurrence in the collecting plate. There are two kinds of pulsed-power supplies; one with pulsed transformers and the other with direct dc switching devices. The latter uses rotary spark gap switches or semiconductor switches. Both have the merits and demerits: the spark gap switches are simple and robust but has short life time, hence, high maintenance cost, whereas the semiconductor switches have long life time but are costly. In this study, A high voltage power supply with superimposing voltage pulse on dc source was developed for EPs. This study describes circuit topology, operating principle of the scheme, and analysis of experimental results on Dong-Hae Power Plant. The pulsed power supply consists of a variable dc power supply with ratings of 60kV, 800mA and pulse generator which is made of high voltage thyristor-diode switch strings, an LC resonant tank and a blocking inductor. The pulse generator generates variable pulse-voltage up to 70kV using a high frequency resonant inverter with a variable dc source. Two prototypes were built and tested on 250MW DongHae power plant to verify the possibility of the commercial use and the normal operation in the transient states.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.129-135
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• 2005

본 연구에서는 펄스 코로나 방전 공정에 의해 $SO_2$와 $SO_2/NO$의 제거효율을 분석하였으며, 여러 공정변수가 제거효율에 끼치는 영향을 체계적으로 조사하였다. 공정변수로서 인가전압, 펄스 주파수, 체류시간, 반응물의 초기 농도(NO, $SO_2$, $NH_3$, $H_2O$, and $O_2$)의 영향을 분석하였다. 인가되는 전압, 펄스 주파수 또는 체류시간이 증가함에 따라 또는 $O_2$와 $H_2O$가 첨가됨에 따라 $SO_2$의 제거효율과 $SO_2/NO$의 동시 제거효율은 증가하였다. 또한, $NH_3$의 초기 농도가 증가할수록 $SO_2/NO$의 제거효율은 증가하였다. 이 실험적인 결과들은 $NO_x$와 $SO_x$를 제거하기 위한 펄스 코로나 방전 공정 장치 설계의 기초 자료로 사용될 수 있다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권2호
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• pp.120-124
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• 2000

In this paper, the effect of magnetic field was measured on NOx(NO+NO2) removal and consumption power for wire-plate plasma reactor with magnetic field applied to electric field vertically. NOx of the simulated diesel engine flue gas were removed by the corona discharge generated by DC, AC and Pulsed voltages in wire-plate reactor. Consumption power increased with discharge voltage. However, when magnetic field was applied to electric field vertically, consumption power slightly decreased. NOx removal rate and arc transition voltage for plasma reactor with magnetic field were higher than those for plasma reactor without magnetic field. Consumption power decreased, however NOx removal significantly increased, when water vapour bubbled by dry air was put into simulated flue gas.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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• pp.31-36
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• 1998

An experimental study has been performed to characterize fundamental aspects of VOCs removal using non-thermal palsma technique. The removed VOCs in the present study are toluene ($C_6H_5CH_3$), ethene ($C_2H_4$), propene ($C_3H_6$) which are typical air pollutants generated from industry and automobile engines. The non-thermal plasma used in the present experiments has been produced in a wire-cylinder reactor with pulsed corona or a packed-bed reactor filled with ceramic bead. These differently generated non-thermal plasma have been visualized with an intensified CCD. The images of non-thermal plasma have been used for optimal design of a corona reactor used in the present study. The experimental results show that the removal efficiencies of VOCs with non-thermal plasma are dependant on the reactivity of VOCs with OH, O, and $O_3$. The results also show that the removal efficiencies of VOCs decrease significantly when VOCs are treated with NO that is also oxidized in the presence of OH, O, and $O_3$.

• 한국안전학회지
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• 제29권3호
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• pp.34-38
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• 2014

In Display such as LCD, LED, and AMOLED or semiconductor related industries are required to have static ionizer in order to produce reliable goods since the ionizer can create balanced ion that is delivered to producing goods to minimize electrical damages when manufacturing. However, the most general type of ionization is called, "Corona Discharge" that has a slight chances to generate unequal and unstable amount of each +/- ion to the target object. Then, the ionization performance will drastically decrease and end up with quality deterioration problem. In this research, our objective to resolve the current issue via applying "Coupling Condenser" on each counter electrodes of Corona discharging type ionizer. The result is that the ion balance was maintained the satisfied range that is within +/-100V when we changed the duty ratio of the High Voltage of Pulse AC about 40 ~ 70%. In addition, when levelling the High Voltage of Pulse AC, the ion balance holds the range within +20 ~ 0V. Even though we have tested the same experiment for a year, we have seen the range changes roughly ${\pm}50V$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1951-1953
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• 2004

In this study, we propose a small high voltage power supply which use a half-bridge ZCS resonant and Cockroft-Walton on circuit, for ESP (Electrostatic Precipitator). This power supply transfers energy from ZCS resonant inverter to step-up transformer and the transformer secondary is applied to the Cockroft-Walton circuit for generating high voltage as discharging source of electrodes. It is highly efficient because its amount of switching losses are reduced by virtue of the current resonant half-bridge inverter, and also due to the small size, low parasitic capacitance in the transformer stage owing to the low number of winding turns of the step up transformer secondary combined with the Cockroft-Walton circuit. From these results, the best operational condition is obtained at the switching frequency of 9 kHz and the duty ratio of 50 % in this ESP.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1806-1808
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• 1998

Tests of pilot-scale plasma DeSOx-DeNOx system using pulsed streamer corona were carried out. The system consists of the reactor with wire-plate electrodes the $30kW_{max}$. MPC type pulse generator, and $1MW_{th}$ pulverized coal combustor as a flue gas source. $NH_3$ and $C_2H_4$ were used to enhance the removal rate. The experimental result on the removal efficiency of SOx/NOx and on the effect of the additives was presented in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2251-2252
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• 1999

In this paper, the effect of magnetic field was measured on NOx removal characteristics for wire-plate plasma reactor with magnetic field applied to electric field vertically. NOx from simulated diesel engine flue gas are decomposed by the corona discharge of DC, AC and Pulsed voltages in wire-plate reactor. Consumption power increased with increasing discharge voltage. When magnetic field was applied to electric field vertically, consumption power decreased. NOx removal rate and arc transition voltage of plasma reactor with magnetic field were higher than those of plasma reactor without magnetic field.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1556-1558
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• 1994

An air/quartz dielectric double barrier pulse discharge has been investigated to develop a novel si lent type ozone generator. It is found that there are very active pulsed coronas occurred in the airgap which are very useful for ozone generation. And, the corona onset voltage of the airgap of the air/quartz double barrier was enfluenced greatly by the airgap of the air/quartz dielectric double barrier, and depended greatly upon the airgap ranged of $0.0{\sim}3.0mm$ and by the quartz tube thickness ranged of $1.75{\sim}2.25mm$.