• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.5
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• pp.199-204
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• 1986

The breakdown phenomena of N2 gas by 13.56MHz electric field are very different from those under steady field. In this paper we analyzed the breakdown phenomena by using electron distribution function and diffusion equation. The second-order differential equation derived from the Boltzmann equation is solved for the electron distribution function. The ionization rate and diffusion coefficient are calculated using kinetic theory formulas. The breakdown condition is that the number of electrons produced by ionization equal the number diffusing to the walls of the discharge chamber. Theses theoretical breakdown electric fields are calculated by the computer and compared with the experimental values.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.2
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• pp.47-53
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• 1984

Breakdown characteristics, specifically, soft breakdown phenomena of the PN junction isolation were studied in terms of their dependence on the mask misaliglment and the amount of process-related defects. Varying the distance between the buried layer and the isolation by intentional misalignment of the isolation masts had no effects on the soft breakdown phenomena except for the change of the breakdown voltage. The soft breakdown phenomena, as characterized as a state of excessive reverse current below the breakdown voltage, were found out to result mainly from the oxidation-induced stacking faults (OSF) introduced during the fabrication process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.540-543
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• 1999

In order to determine what indluences the interfacial breakdown in EPDM/XLPE laminates. We studied the interfacial breakdown phenomena at several interfacial conditions. Breakdown strength in laminates pasted with silicone oil was higher than that with silicone grease. As a function of heat treatment time in a vacuum, interfacial breakdown strength increased much in XLPE/EPDM laminates pasted with silicone grease but increased a little in that with silcone oil. FT-IR spectrum of silicone oil was similar to that is silicone grease. FT-lR spectrum of silicone oil was not changed by the heat treatment in a vacuum, but in silicone grease another peak appeared.

• Proceedings of the KIEE Conference
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• 2008.09a
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• pp.227-228
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• 2008

In this paper, the behaviour of charge carriers near the metal/polymer interface and its effects on conduction and breakdown phenomena are discussed. The metal/polymer interface strongly affects tarrier injection space charge formation and breakdown phenomena. Based on their experimental results, the physical backgrounds of the interfacial phenomena are explained.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2313-2314
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• 2008

In this paper, the behaviour of charge carriers near the metal/polymer interface and its effects on conduction and breakdown phenomena are discussed. The metal/polymer interface strongly affects carrier injection, space charge formation and breakdown phenomena. Based on their experimental results, the physical backgrounds of the interfacial phenomena are explained.

• Progress in Superconductivity and Cryogenics
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• v.5 no.2
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• pp.46-50
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• 2003

In the dielectric insulation design of any high temperature superconducting (HTS) apparatus as well as HTS fault current limiter in the electrical power systems, the breakdown characteristics of cryogenic coolants such as liquid nitrogen ($LN_2$) are an important factor of the insulating engineering. Previous reports concerned with the breakdown characteristics of liquid nitrogen have pointed out that bubbles and gaseous nitrogen have a treat influence on their breakdown phenomena, However, useful data for practical insulation design of HTS fault CUITent limiter operating at subcooled L$N_2$ have not been obtained enough. Therefore, this paper presents an experimental investigate of breakdown phenomena in liquid nitrogen under AC voltage, And, we observed the breakdown voltage (BDV) of liquid nitrogen with lowering temperature. The Weibull plots of the breakdown voltage of subcooled $LN_2$ for the needle-plane electrode with d= 10 mm are studied, The dependence of breakdown voltage for needle-plane and pancake coil-pancake coil electrode on temperature is illustrated, The relationship between the AC breakdown characteristics and the temperature were clarified.

• 전기의세계
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• v.27 no.6
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• pp.76-83
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• 1978

This paper reveals the results of fundamental experiments with the breakdown strength- and treeing phenomena, by A.C voltage and impulse voltage, of cross-linked polyethylene insulator, respectively compared in each case of the various specimens; nonvoid, air void, water void, oil void and oil impregnated one, all articially made. In this research, the V-t and V-n characteristics are investigated by means of the Weibull distribution and are analysed the characteristics of fatigue breakdown caused by the A.C and impulse voltage. Based on numerous tests, treeing effect and treeing breakdown mechanism is investigated through microscopic photographs taken to clarify the shapes of each tree and treeing breakdown phenomena.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.398-403
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• 1999

Studies on the electrical treeing deterioration and dielectric breakdown phenomena in the polymeric insulator of polyethylene and epoxy resin were carried out. Block type samples with needle-plane electrode geometry were electrically stressed and the tree pattern from the needle tip was observed. In LDPE the density of electrical tree was very high and its pattern was bush type. For the case of XLPE, branched tree was observed. As temperature and SN content increased, the dielectric breakdown voltage decreased and the treeing phenomena became more complicated. Fan type cracks were observed around the conducting tree path in the brittle DGEBA/MDA system.

• Journal of the Korean Institute of Telematics and Electronics
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• v.11 no.3
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• pp.22-26
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• 1974

The effects of anisotropic mechanical stress applied normal to the surface of p-n junctions have been investigated. As the stress increased, the breakdown voltage was decreased and the breakdown mode became softer. Within a certain limitation in the applied stress, the above phenomena werw reversibbe, though relaxation and hysteresis phenomena were observed. The time constant of relaxation depended upon the shape of the stressing tip, but for the given tip and device a unique time constant was obtained. The stress.dependence of breakdown voltage showed a good linearity up to about 3.0${\times}10^4$ kgw/$\textrm{cm}^2$, when the flat tip of radius 15$\mu$ was used, and the temperatere-dependence of breakdown voltage under the stress also showed a good linearity in the temperature range of 100 to $300^{\circ}K$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.137-141
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• 1996

This paper deals with the prebreakdown phenomena of $SF_{6}$ gap stressed by non-oscillating and oscillating impulse voltages in a strong inhomogeneous field disturbed by a fred needle shaped-protrusion on the earth-side electrode. The breakdown voltage-time characteristics were measured for both positive and negative polarities and over the gas pressure range of 0.1∼0.5 MPa, and the temporal developments of the 77breakdown were observed by a shunt of 50 n. The dependence of the leader stopping time on the gas pressure were obtained. The local field enhancement due to the space charges, which is produced by the streamer corona, has influence with the electrical breakdown of the test gap. The test streamer corona is oxy a necessary condition for the electrical breakdown and the subsequent ionization activities launch the leader at the local field region.