• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.827-832
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• 2008

One of the most important issues in AC PDP is luminance and luminous efficacy. To improve the luminance and luminous efficacy, new sustain electrode structure which contains long discharge gap is necessary. However, it causes a rise of firing voltage. In this experiment, a new structure is proposed in order to solve this problem. To drop the firing voltage, the hump shaped electrode is inserted into the forward area of the main discharge gap. The experimental results show that proposed structures with 160um discharge gap have high firing voltage by 38V, high luminance by 30% and high luminous efficacy by 15% compared with conventional type having 60um discharge gap. In addition, the proposed structure with hump electrode shows lower firing voltage by 24V compared with the test panel with 160um discharge gap which doesn't have hump electrode though they have similar luminous efficacy.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.3
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• pp.25-34
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• 2001

In this paper, discharge lamp ozonizer(DLO) of a new discharge type using superposition of gaseous electrical discharge for environment improvement was designed and manufactured. DLO is equipped with 3 electrodes(central ground electrode of discharge lamp type internal high voltage electrode of mesh type and external high voltage electrode of spiral type), and it is composed of double gap(gap between discharge lamp and internal electrode, gap between discharge lamp and external electrode). Internal and external electrodes are respectively applied AC high voltage which has 180[$^{\circ}$] phase difference. Ozone is generated by overlaying of each silent discharge which is respectively came from two gaps. At the moment discharge characteristics and ozone generation characteristics of DLO were investigated in accordance with quantity of supplied gas, discharge power and the number of DLO. When ozone generated by DLO was in contact with NO gas, removal characteristics was excellent, so it confirmed that DLO could be used as air environment improvement facility.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.539-540
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• 2006

In this paper, We examine that characteristics of formative electret with polymer film and electric charge storage using grid corona discharge. compound polymer of fluorine resin used for material in electret because of high electric charge accumulation, excellent electrical and physical characteristic. All experiments were carried out with circular samples of $Teflon^(R)FEP$ film, 12.5[${\mu}m$] thick. As experiment variables, we used voltage, electrode thickness, discharge electrode gap, and discharge time. According to this variables, we studied on characteristics of formative electret and electric charge storage. Additionally we make a comparative study of the result between the grid corona discharge and needle electrode discharge.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.104-109
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• 2013

Tin and Tinoxide nanoparticles were prepared by arc-discharge nanopowder process. The negative electrode were fabricated using Tin and Tinoxide nanopower. The microstructure and electrochemistry properties were investigated and compared between Tin and Tinoxide. The oxidation film has microstructure of core/shell type and the shell which was attached around Tin nanoparticle consisted of amorphous $SnO_2$. The shape of Tinoxide nanoparticles was formed with irregular shape in comparison with Tin particle. Initial discharge capcity of Tinoxide electrode possesed about 1000mAh/g, which is about 320mAh/g higher than Tin electrode. Irreversible capacity of Tin electrode is much higher than Tinoxide. The cycle performance of Tinoxide electrode was indicated that is batter than Tin. The Tin negative electrode lost most of capacity after 4 cycle but Tinoxide electrode still retained the capacity. The Tinoxide does show some promise as Li-ion battery anode due to their large reversible capacity at low potentials.

• Journal of the Korean institute of surface engineering
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• v.50 no.2
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• pp.108-113
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• 2017

We investigated the effect of graphite electrode geometry and combination on nanocarbon material synthesis using underwater discharge plasma(UDP). The UDP system consists of two graphite electrodes and beaker filled with de-ionized water. A high voltage of 15 kV with a frequency of 25 kHz is applied to produce UDP using an alternating-current power source. The UDP system with conical electrodes produced the largest amount of products due to the concentration of electrical fields between electrodes. In addition, hollow-shaped stationary electrode and conical-shaped moving electrode stores discharge-induced bubbles and maintains longer reaction time. We found from Raman spectroscopy and electron microscopy that high quality carbon nanomaterials including carbon nanotubes are synthesized by the UDP system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.492-498
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• 2012

Characteristics of DBD(Dielectric Barrier Discharge) plasma actuator as design parameters were investigated for plasma flow control. Flow velocity and power consumption of the DBD plasma actuator were measured according to the design parameters such as discharge voltage and frequency, gap, width and length of electrode, and the thickness of dielectric barrier. The flow velocity and power consumption increased as the discharge voltage and frequency increased. As the electrode gap increased, the flow velocity increased with decreasing the power consumption, whereas high voltage was required for the plasma discharge. The flow velocity increased as the upper-electrode width decreased, and as the lower-electrode width increased at the constant power consumption. The performance of the DBD plasma actuator can be estimated at the given discharge and geometry conditions.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1512-1516
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• 2018

The power system and control system constantly reveals surge voltage such as switching surge of lighting devices and power conversion devices, operating and stops surge of rotating devices, charge & discharge surge, opening & closing surge of circuit breakers and the like. Such a surge voltages can cause damage or malfunction of the element such as CPU, Memory, semiconductor etc. In the industry, in order to protect the system from the surge voltage, a surge protector with low discharge starting voltage, fast response time, and low capacitance is required, and technical development research for that is ongoing. In this paper, in order to solve the problem of the existing GDT discharge tube not discharging from the transient voltage which is higher than the commercial voltage and lower than the discharge voltage of the discharge element, we have developed a discharge element having the control electrode & control circuit. The discharge element having the control electrode and the control circuit can control the discharge voltage according to the needs of the consumer and can satisfy the requirement of the discharge element and the technology of the surge protector downsizing technology and the surge protection technology. It is judged to be effective for development.

• Electrical & Electronic Materials
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• v.8 no.5
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• pp.564-571
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• 1995

This paper deals with the arc discharge characteristics of kerosene oil as a basic study on electrical discharge machine. Using needle electrode the discharge voltage, discharge current, discharge energy and the shape of discharge crater are measured. In consequence, it becomes clear that the discharge crater(depth, height, diameter) is depending on the discharge energy. Rapid increase in depth, height and diameter of discharge crater was observed during initial discharge, where discharge energy is large. However, rather slow decrease of those values was found when discharge energy is low or N is more than 3. As the ratio of $I_p$$T_on$ increase, the shape of discharge crater gets near circle. The protuberances of the discharge crater were not formed by the melted needle electrode but by the that of work piece.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.261-267
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• 2008

One of the most important issues in fence-type PDP is low luminance and luminous efficiency. To improve luminance and luminous efficiency, new sustain electrode structure which contains long discharge gap is necessary. However, it causes rise of firing voltage. In this paper, a new fence electrode structure is proposed in order to solve these problems. To drop the firing voltage, tow hump shaped electrodes is added on the main discharge electrode, and distance between two humps is controlled. The experimental results show that the test panel with the narrow horizontal gap(40um) between two humps shows low firing voltage by 17V compared with 80um gap in spit of similar luminance and luminous efficiency.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.5
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• pp.85-90
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• 2012

In this paper, it was investigated experimentally that diameter and polarity variation of corona wire electrode affected to ozone generation of the ozone generator using a wire-to-plate type electrode. The change in the diameter(D) of the corona wire electrode has a great effect upon ozone generation, higher influence appears in the positive corona discharge than the negative corona discharge. In the case of D=0.50[mm], maximum ozone generation and power efficiency could be obtained. However, in the case of smaller D than this, the ozone generation and efficiency decreases slowly and in the case of larger D, the ozone generation decreases rapidly. It means performance decline as an ozone generator. Therefore, ozone generation and power efficiency would increase through simple optimization of the corona electrode specification.