• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.627-630
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• 2002

본 논문에서는 플라즈마 디스플레이 패널(PDP)의 높은 소비 전력을 줄이기 위해 요구되어지는 에너지 회수회로를 제안한다. 제안하는 회로는 기존의 회로와 비교하여 저가형 구조를 가지며 효율을 증대 시킬 수 있는 장점을 가진다 본 회로는 유지 구간 동안 두 번의 공진을 수행하게 된다. 패널과 병렬로 결합된 인덕터와 외부 캐패시터 사이에서 발생하는 첫 번째 공진은 정$\cdot$부의 선택적인 펄스를 발생시키기 위해 이용되고, 스위치 오프 구간동안 순간적으로 발생되는 인덕터와 패널사이의 두번째 공진은 PDP의 용량성 변위 전류에 의한 에너지를 회수하게 된다. 제안하는 회로의 동작원리와 설계절차를 제시하였으며, 7.5인치 패널을 이용한 시작품을 제작하여 시뮬레이션과 실험결과를 통해 타당성 을 검증하였다.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.631-634
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• 2002

Plasma Display Panel의 기술은 급격하게 발전하고 있지만, 여전히 몇 가지 문제를 해결하기 위해 다각적인 접근이 이루어지고 있다. 동화상의 윤곽제거, 광 대비 향상을 통한 화질의 개선, 신뢰도 및 전력 효율을 개선하는 등의 문제가 여기에 해당되며 그 중에서도 특히, 전력 효율을 향상시키기 위해서는 PDP의 발광효율을 높이는 것과 함께 기체방전과는 직접적인 관련이 없이 구동과정에서 발생하게 되는 불필요한 전력 소모를 최소화하여야한다. 본 논문에서는 이러한 전력소모를 최소화하기 위한 새로운 형태의 고효율 에너지 회수 회로를 제안하고 시뮬레이션을 통해 그 동작을 확인하였다 그리고 제안하는 회로를 실제 7.5 인치 패널에 연결하고, 200 (kHz)에서 실험하여 제안한 에너지 회수 회로의 타당성을 검증하였다.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.717-721
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• 2003

Two non-conventional HVDC converter arrangements are compared. These include the Capacitor Commutated Converter (CCC) in which series capacitors are included between the converter transformer and the valves, and the Controller Series Capacitor Converter (CSCC), based on more conventional topology, in which series capacitors are inserted between the AC filter bus and the AC network. Results show that both options have comparable steady state and transient performance. Danger of ferroresonance with the CSCC option is eliminated by controlling the amount of series compensation. The dynamic performance simulations is peformed by PSCAD/EMTDC

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.920-927
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• 1998

This paper proposed that an Analysis of a partial resonant AC-DC converter for high power and power factor operates with four choppers connecting to a number of parallel circuit. To improve these, a large number of soft switching topologies included a resonant circuit have been proposed. And, some simulative results on computer are included to confirm the validity of the analytical results. The partial resonant circuit makes use of an inductor using step-down and a condenser of lose-less snubber. The result is that the switching loss is very low and the efficiency of system is high. And the snubber condenser used in a partial resonant circuit makes charging energy regenerated at input power source for resonant operation. The proposed conversion system is deemed the most suitable for high power applications where the power switching devices are used

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.109-110
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• 2000

Sputtering yield of MgO film in the AC-PDPs has been calculated by Monte Carlo simulation of ion scattering. In the ion energy range less than 50 eV, the sputtering yield is 4 ${\times}$ $10^{-4}$ for Xe ions and it is between 0.1 and 0.01 for He, Ne, and Ar ions. The erosion rate is estimated about $25{\AA}$ per hour for Xe ions in an actual PDP plasma for sustain and full white mode.

• International Journal of Fluid Machinery and Systems
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• v.8 no.1
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• pp.13-22
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• 2015

This study presents a simulation model of a heat pump air conditioning system with a variable capacity compressor and variable speeds fans for electric bus. An experimental sample has been developed in order to check results from the model. Effects on system performance of such working conditions as compressor speed, evaporator fans speeds and the condenser fans speeds have been simulated by means of developed model. The results show that the three speeds can be adjusted simultaneously according to actual working condition so that the AC system can operate under the optimum state which the control objects want to achieve. It would be a good and simple solution to extend the driving ranges of EVs because of the highest efficiency and the lowest energy consumption of AC system.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.273-277
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• 2002

In the electrode fabrication of unit cell, we found that optimal the electrochemical characteristics were obtained with at 90 wt.% of activated carbon(BP-20), 5 wt.% of conducting agent(Ppy, Super P) and 5 wt.% of P(VdF-co-HFP)/PVP mixed binder. The electrochemical characteristics of unit cell with Ppy improver were as follows : 37.6 F/g of specific capacitance, 0.98 $\Omega$ of AC-ESR, 2.92 Wh/kg and 6.05 Wh/L of energy density, and 754 W/kg and 1,562 W/L of power density. It was confirmed that internal resistance were reduced due to the increase of electrical conductivity and filling density by the introduction of conductivity agent, and content of conducting agent was suitable in the range of 4~6 wt.%. According to the impedance measurement of the electrode with conductivity agent, we found that it was possible to charge rapidly by the fast steady-state current convergence due to low equivalent series resistance(AC-ESR), fast charge transfer rate at interface between electrode and electrolyte, and low RC time constant.

• Proceedings of the Safety Management and Science Conference
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• 2003.11a
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• pp.335-343
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• 2003

In the electrode fabrication of unit cell, it was ascertained that electrochemical characteristics were greatly increased with 90 wt.% of BP-20, 5 wt.% of Super P and 5 wt.% of mixed binder [P(VdF-co-HFP) : PVP =7 : 3] The self-discharge of unit cell showed that diffusion process was controlled by the ion concentration difference of initial electrolyte due to the characteristics of Electric Double Layer Capacitor (EDLC) charged by ion adsorption in the beginning, but this by current leakage through the double-layer at the electrode/electrolyte interface had a minor effect and voltages of curves were remained constant regardless of electrode material. The electrochemical characteristics of 2.3 V/3,000 F grade EDLC were as follows: 0.35 m of DC-ESR (100 A discharge), 0.14 mof AC-ESR (AC amplitude 100 mV), 2.80 Wh/kg (3.73 Wh/L) of energy density and 4.64 kW /kg (6.19 kW/L) of power density. Power output was compatible with electric vehicle applications, uninterrupted power supply and engine starter, in due consideration of Ragone relations.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.11
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• pp.1647-1650
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• 2017

Bus bars are used in place of cables because they can carry more electrical energy with the same volume of conductors. This paper deals with the electrical properties of ceramic coating material for busbars. A ceramic coated samples were prepared for the electrical properties test. There are two types of samples. One is a sample without degradation, and the other is a sample degraded for 30 days. Four electrical properties tests were carried out in accordance with domestic standards. Four electrical characteristics tests are AC dielectric breakdown, V-t, lighting impulse dielectric breakdown, and discharge arc. Both samples showed excellent electrical properties, and the ceramic coating material is very good insulating materials for bus bar.

• Journal of Power Electronics
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• v.14 no.5
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• pp.874-881
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• 2014

This study presents a single-phase power factor correction AC-DC converter that operates in discontinuous conduction mode. This converter uses the pulse-width modulation technique to achieve almost unity power factor and low total harmonic distortion of input current for universal input voltage $90V_{rms}$ to $264V_{rms}$) applications. The converter has a simple structure and electrical isolation. The magnetizing-inductor energy of the transformer can be recycled to the output without an additional third winding. The steady-state analysis of voltage gain and boundary operating conditions are discussed in detail. Finally, experimental results are shown to verify the performance of the proposed converter.