• Journal of IKEEE
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• v.19 no.3
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• pp.366-370
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• 2015

This paper proposes an alternating battery discharge method by balancing discharge time of battery cells, which significantly increases battery lifetime. In the conventional method, several battery cells are alternately discharged to make battery recovery effect, and this increases battery lifetime. In this case, there are some overlap intervals where several battery cells are ON to avoid system power cut-off, but this makes several problems due to the voltage differences of battery cells. To mitigate these problems, discharge time of battery cells are controlled to make battery cell voltages as equal as possible. Measurements show that the battery lifetime is exxtended by 19.2% in the proposed method.

• Journal of Information Display
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• v.2 no.1
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• pp.24-33
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• 2001

The characteristics of the reset and the address discharges of an alternating current Plasma Display Panel (ac PDP) were studied using 2-dimensional numerical discharge cell simulation. We investigated the wall charge variations during the reset discharge adopting ramping reset pulse and the subsequent addressing discharge. The roles of the ramping reset scheme can be divided into two stages, each electrode gathers wall charges during ramping-up of the initial stage and the built-up wall charges are lost during ramping-down of the later stage. Address discharge does not only change the wall charge distributions on the address and the scan electrodes but also on the sustain electrode. The increase in the wall charges on the sustain electrode was observed with the variation of the applied voltage to the sustain electrode during the address period. The increase of the applied voltage to the sustain electrode during the address period is expected to induce the decrease of the sustain voltage during the display period.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.503-506
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• 2004

In this paper, we suggest a new driving waveform for stable address discharge in AC PDP without the reduction of contrast ratio. To analyze the influence of cross-talk between discharge and non-discharge cells and verify that proposed waveform shows a stable address discharge, we measured the address discharge delay time. The proposed waveform shows the reduction of the cross-talk and concurrently the improvement of address voltage margin compared with those of selective reset waveform having one reset period in 1TV-Field..

• Journal of IKEEE
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• v.18 no.1
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• pp.96-105
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• 2014

This paper proposes a battery lifetime enhancement method based on the nonlinear discharge charisteristics called recovery effect. In general, the stored energy in a battery is considered in the prediction of battery lifetime. However, due to the chemical reaction in a battery, more energy can be drawn from a battery when it is not continuously but intermittently discharged, which is called recovery effect. In the proposed method, several battery cells are alternately discharged, and some battery cells rest while maintaining the system power supply. This makes recovery effect of battery cells, which extends battery lifetime. In the experiment, battery lifetime increases about 7% in the alternating discharge of two battery cells, when compared with conventional parallel discharge.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.577-582
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• 2007

The plasma display panel is an image expression display using gas discharge plasma. However, gas discharge characteristics vary with temperature as gas discharge is sensitive to temperature. The discharge time lag extends a lot in low temperature and it is known as the cause which hinders high speed addressing which is essential for the size enlargement of the panel. Accordingly this research aims at identifying the temperature-dependent discharge characteristic. The lower temperature becomes, the longer addressing discharge time lag becomes. Particularly the statistical time lag extends much in low temperature. The increasing of electric field shortens discharge time lag in low temperature. Also, when priming particles are sufficiently supplied, stable discharge can be performed regardless of the influence of temperature.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.5
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• pp.516-518
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• 1990

We have derived the equation which involves the variation of electron energy with time in a lowly ionized plasma when a low alternating electric field is applied. We consider only elastic collisions between electrons and neutral atoms. This equation is solved using the 4th-order Runge-Kutta method, and applied to argon gas discharge which is driven by source frequency of 100, 1K, 10K, 100K, and 1M (Hz). The results show that the variation of electron energy becomes flat with higher frequencies.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1060-1062
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• 1999

Pulsed Nd:YAG laser is used widely for materials processing and instrumentation. It is very important to control the laser energy density in materials processing by a pulsed Nd:YAG laser. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, the alternating charge-discharge system was designed to adjust a pulse repetition rate. And the parallel mesh is added to increase laser output power. This system is controlled by one chip microprocessor and allows to replace an expensive condenser for high frequency to a cheap condenser for low frequency. In addition, we have investigated the current pulse shape of flashlamp and the operating characteristics of a pulsed Nd:YAG laser. As a result, it is found that the laser output of the power supply using the parallel mesh and the alternating charge-discharge system is not less than that of typical power supply. As the pulse repetition rate rises from 10pps to 110pps by the step of 20pps at 1000V and 1200V, it is found that the laser efficiency decreases but the laser output power increases about 5W at each step.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2204-2206
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• 1999

Pulsed Nd:YAC laser is used widely for materials processing and instrumentation. It is very important to control the laser energy density in materials processing by a pulsed Nd:YAG laser. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, the alternating charge-discharge system was designed to adjust a pulse repetition rate. This system is controlled by one chip microprocessor and allows to replace an expensive condenser for high frequency to a cheap condenser for low frequency. In addition. we have investigated the current pulse shape of flashlamp and the operating characteristics of a pulsed Nd:YAG laser. As a result, it is found that the laser output of the power supply using the alternating charge-discharge system is not less than that of typical power supply. As the pulse repetition rate rises from 30pps to 120pps by the step of 30pps at 1200V, it is found that the laser efficiency decreases but the laser output power increases about 6W at each step.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.12
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• pp.606-615
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• 2004

The discharge characteristics of a ramp reset waveform in the alternating current plasma display panel(ac PDP) were studied using a 2-dimensional numerical simulation. We analyzed the wall charge variation during the reset discharge, address discharge and sustain discharge adopting a ramp reset waveform. Then we investigated the principal parameters for a successful discharge. In this paper, we suggest a new parameter, printing particles' density and its effects on the stability of the ramp discharge. The maximum current flows of the three electrodes during the ramp reset period were decreased with the increase in the priming particles's density which was explained with the wall charge characteristics and the current flow characteristics obtained by a 2-D simulation.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.317-320
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• 2013

Partial discharge resistance for the epoxy systems with two diluents was investigated in the rod-plane electrodes arrangement, and the effect of electric frequency on the partial discharge resistance was also studied. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and 1,4-butanediol diglycidyl ether (BDGE) or polyglycol (PG) as a reactive diluent was introduced to the DGEBA system, in order to decrease the viscosity of the DGEBA epoxy system. BDGE was acted as a chain extender, and PG acted as a flexibilizer, after the curing reaction. To measure the partial discharge resistance, 5 kV alternating current (ac) with three different frequencies (60, 500 and 1,000 Hz) was applied to the specimen in a rod-plane electrode arrangement, at $30^{\circ}C$. PG had a good effect, while BDGE had a bad effect on the partial discharge resistance of the DGEBA system, regardless of the electric frequency.