• 한국전기전자재료학회논문지
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• 제28권9호
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• pp.587-592
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• 2015

In this study, the electrification voltage of electrostatics for silicone rubber sample($4cm{\times}4cm{\times}0.103cm$) following immersion with contaminants of 2 ml, 5 ml, 10 ml for six hours has been measured in through the applied voltage of 10 kV DC at temperature of $80^{\circ}C{\sim}110^{\circ}C$, humidity of 50%~90%. The results of this study are as follows. In case the contaminants is constant, it found that the electrification voltage of electrostatic decreased with increasing temperature and humidity to $35^{\circ}C$, 90%. In case of 2 ml of contaminants concentration, it found that the electrification voltage of electrostatic decreased with increasing temperature and humidity to $35^{\circ}C$, 50%. In case of the sample at temperature of $15^{\circ}C$ and humidity of 50%, it found that the electrification voltage of electrostatic decreased with increasing contaminants to 10 ml.

• 한국전기전자재료학회논문지
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• 제27권8호
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• pp.522-527
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• 2014

In this study, using the silicone rubber sample of $4cm{\times}4cm{\times}0.1cm$ for low voltage cable, the electrostatic electrification properties of three samples that the conductive Al of 0%, 25%, and 50% is attached to the surface of sample was measured. The following conclusion was obtained through this experiment. 1) In case of the sample which has the Al area of 50%, the higher the humidity to 90% in the temperature of $10^{\circ}C$, the electrostatic electrification voltage was reduced about 0.25 kV to 0.02 kV, and it confirmed that the electrostatic electrification voltage was in constant about 0.02 kV in the temperature over $20^{\circ}C$. 2) Increasing the Al area of samples of 0%, 25%, and 50% in temperature of $10^{\circ}C$, it confirmed that the electrostatic electrification voltage was reduced by about 2.67 kV, 2.02 k, 0.21 kV. 3) This study shows that the conductor, followed by temperature and humidity affects the electrostatic electrification voltage.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.357-360
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• 1995

Since the streaming electrification phenomena of transformer were made clear on 1970s, many researches have been continued on the improvement of the transformer. This paper describes the effect of additive (BTA, DBPC) and temperature on the streaming electrification of the various materials. The streaming current in the various materials decreases in proportion to the concentration of BTA, results in the inverse electrification. We believe that these results will contribute to the optimal design of HV large-capacity transformer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.332-335
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• 1995

Electrification pipe modeled on the oil path of the high power transformer is designed and manufactured. Distributions of oil flow velocity are simulated as spacer form in the electrification pipe. Streaming currents are investigated as each electrification pipe. The surface oil velocity of spacer is small the streaming current.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.336-343
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• 1999

This paper presents development of the program which calculates the electric quantities such as current, voltage at each pan of railway electrification system in static state. The purpose of this program is to estimate the adequacy of railway electrification system through simulations. And it contributes the estimations for optimal railway electrification system by calculating the maximum of current and voltage. The results are represented through GUI(Graphic User Interface) for user to understand easily.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 춘계학술대회 논문집
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• pp.333-340
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• 2001

This paper presents development of the program which calculates the electric quantities such as current, voltage at each element of railway electrification system in static state. The purpose of this program is to estimate the adequacy of railway electrification system through simulations. And it contributes the estimations for optimal railway electrification system by calculating the maximum current and voltage. The simulation program is coded through GUI(Graphic User Interface) technique for user to operate easily.

• 전기의세계
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• 제24권5호
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• pp.21-30
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• 1975

These studies aim to support technically the National Rural Electrification Program now in progress by analyzing several engineering problems in regard to the program and then suggesting some appropriate solutions or measures. The contents of these studies are divided into three categories; (1)optimized distribution systems for the rural electrification, (2)optimized rural illumination and (3)single-phase operation of three-phase motors.

• 전기학회논문지
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• 제61권4호
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• pp.580-584
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• 2012

The insulating oils perform a cooling and insulation action in electric power transformer. The mineral oil has immanent fire dangerousness and environmental contamination problem. Vegetable insulating oil has higher ignition point, flash point and more excellent biodegradability than conventional mineral oil. In a real oil-filled transformers, some of the power is dissipated in the form of heat. And transformer require the heat to be removed from the winding and insulator by forced convection of the insulating oil. The flow electrification occurs when insulating oil was forced to be circulated. In this paper, influence of temperature, velocity of flow, and insulating pipe and diameter on streaming electrification of vegetable insulating oil was investigated using forced circulation apparatus. Temperature effects were most significant, and it showed a peak in the temperature $30^{\circ}C$ to $35^{\circ}C$ at insulating and copper pipe. The change of flow electrification according to area variety could be checked by change of diameter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1615-1618
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• 1994

This paper studied the streaming electrification of the U.H.V. transformer with the spinning cylinder system, and compared and analyzed it with the conventional forced flowing system which uses a pump or gas for oil flowing. Also, accumulated surface voltage in its electrified material was measured with the electrostatic voltmeter, and the effect of insulation oil aging was measured. As results, in spinning cylinder system, characteristics of the streaming electrification to its rotational speed and oil temperature are same tendency as those of tile forced flowing system and it showed the spinning cylinder system is useful to study the streaming electrification. And, aging of insulation oil increases the electricity of streaming electrification at initial stage of aging.

• 전기학회논문지
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• 제60권2호
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• pp.338-343
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• 2011

In this paper, the FT-IR, conductivity and flow electrification phenomena of Vegetable oils were discussed. Vegetable oil has high flash point and eco-friendly properties compared to conventional mineral oil. Accelerated aging transformer oil samples produced in the oven at 140[$^{\circ}C$] for 500 hours, 1000 hours, 1500 hours, 2000 hours. Serial device to measure the flow electrification phenomena was designed and fabricated. Pico ammeter and the Labview data measurements were utilized. The effects of Temperature and antistatic agent on fluid flow electrification were investigated. Both Mineral and vegetable oil showed similar trends for temperature change. The polarity reversal occurred in mineral oil with antistatic agent above 10 ~ 30[ppm] and in vegetable oil with antistatic agent above 5[ppm].