• 한국전기전자재료학회논문지
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• 제21권12호
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• pp.1118-1123
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• 2008

High voltage multilayer ceramic capacitors (MLCCs) are classified into two classes-those for temperature compensation (class I) and high dielectric constant materials (class II). We manufactured high voltage MLCC with temperature coefficient characteristics of C0G and X7R and studied the characteristics of electric properties. Also we studied the characteristics of dielectric breakdown voltage (V) as the variation of thickness in the green sheet and how to pattern the internal electrodes. The dielectric breakdown by electric field was caused by defects in the dielectric materials and dielectric/electrode interface, so the dielectric thickness increased, the withstanding voltage per unit (E) thickness decreased. To overcome this problem, we selected the special design like as floating electrode and this design affected the increasing breakdown voltage(V) and realized the constant withstanding voltage per unit thickness(E). From these results, high voltage application of MLCCs can be expanded and the rated voltage can also be develop.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.335-338
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• 2008

With the improvement of industrial society, the high quality electrical energy, simplification of operation and maintenance, ensuring reliability are being required Also we request urgently change a $SF_6$ for an environment friendly gas insulation material. In this paper the experiments of breakdown characteristics by pressure and gap change of Imitation-Air in model GIS(Gas Insulated Switchgear) were described. Also assess of breakdown characteristics about Imitation-Air and $SF_6$. It is considered in this paper that the results are fundamental data for electric insulation design of Distribution Power Facilities which will be studied and developed in the future.

• Journal of Electrical Engineering and Technology
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• 제5권4호
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• pp.646-652
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• 2010

This paper investigates a method to improve the breakdown voltage characteristics of a gas discharge arrester (GDA) for a surge suppressor. The middle electrode is inserted between two terminal electrodes. Voltage application to the electrode synchronized and amplified by the impulse voltage decreases spark overvoltage from 45% to 57.6%. The decrease is caused by higher voltage slope, as opposed to applied impulse voltage (by 5.5 to 6.2 times). In addition, the GDA model using ATP-Draw was used to analyze the operation characteristics of GDAs. The test and simulation results agree to within 2% when the trigger source was used.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1407-1409
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• 1998

It was investigated that space charge characteristics and Breakdown characteristics of XLPE/EPDM laminates as a function of interfacial condition. When the chemical A was pasted in laminate interface, there was little space charge in XLPE/EPDM interface and it was shown that breakdown strength of XLPE/EPDM laminate was influenced by laminate condition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.275-278
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• 1990

This study investigated electrical characteristics of solid and liquid epoxy rosins by measuring dielectric breakdown and dielectric loss when epoxy resins were exposed to a mixing cure, i.e., Fusion Blend Method. It was found that mixing epoxy resins were superior to dielectric breakdown and has shorter curing time compare with those of pure liquid epoxy resins.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.437-440
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• 2000

In this study, the interfacial dielectric breakdown phenomenon of interface between Epoxy and Rubber was discussed, which affects the stability of insulation system of power delivery devices. The breakdown strength of specimens are observed by applying high AC voltage at the room temperature. The breakdown times under the constant voltage below the breakdown voltage were gained. As constant voltage is applied, the breakdown time is proportion to the breakdown strength. The life exponent n is gained by inverse power law and the long time breakdown life time can be evaluated.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.460-461
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• 2007

In this paper, we studied the properties of a cable insulate capacity between surfaces with the variation of the interfacial breakdown. As a function of silicon oil, the variation of pressure and interfacial roughness were investigated. The insulate trouble of a power cable is out of the interfacial parts, which breakdown the insulate breakdown capacity in a power cable. In this study, the analysis of electric field and the phenomenon of interfacial breakdown were improved by increased interfacial pressure, decreased surface roughness, and oil. And It was shown that interfacial breakdown LSR-XLPE insulators is higher that of EPDM-XLPE.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.177-179
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• 1990

Recently, it is reported that the behaviour of PECVD under high electric field and current condition has a major effect on MNS device degradation. In this paper, we evaluated the breakdown and TDDB characteristics of Laser assisted PECVD SiN films which is introduced new deposited method. And also, long term insulator breakdown reliability is described by examing time dependent dielectric breakdown under positive voltage. Failure tines against electric field are examined and acceleration factors are obtained for each case. From these data, breakdown wearout limitation for Laser Assisted PECVD SiN film can be characterized.

• 한국자동차공학회논문집
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• 제7권5호
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• pp.172-177
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• 1999

In this paper, the physical and electrical properties of the synthetic fluids No. 2 class Ⅶ used the insulating oils for automobile ignition coil are studied. Also, benzotriazole(BTA) as the streaming electrification suppressant additive is added to the oil, and the change of physical and electrical properties due to different BTA concentration is investigated. To investigate the electrical characteristics, the breakdown strength of each specimen by an experiment for AC breakdown and the changes of conductivity by measuring volume resistivity are analyzed. It is considered that the effective content of BTA as charge suppressant additive is about 10[ppm] from the results of AC breakdown and volume resistivity test.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.278-282
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• 2007

In the complex insulation system that is used in extra high voltage(EHV) devices, according to the trend for electric power equipment of high capacity and reduction of its size, macro interfaces between two different bulk materials which affect the stability of insulation system exist inevitably. In this paper, the dielectric strength decrease of the macro interfaces between epoxy and ethylene propylene diene terpolymer(EPDM) was estimated by using the applied voltage to breakdown time characteristics. Firstly, the AC short time dielectric strength of specimens was measured at room temperature. Then, the breakdown time was measured under the applied constant voltage which is 70% of short time breakdown voltage. With these processes, the life exponent n was determined by inverse power law, and the long time breakdown voltage can be evaluated. The best condition of the interface was LOS(low viscosity(350 cSt) silicone oil spread specimen). When 30 years last on the specimens, the breakdown voltage was estimated 44% of the short time breakdown voltage.