• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.153-156
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• 1998

구형도파관의 넓은 면에 축방향 슬롯을 파고 또 각각의 슬롯을 축방향으로 배열하였 때의 원거리 방사패턴을 구하는 과정을 보였으며 측정된 결과와 계산결과를 비교하였다. 방사전자계는 슬롯의 표면에 유기되는 등가의 자기전류로부터 계산할 수 있으며 임의의 개수를 가지는 배열안테나의 경우에는 각각의 슬롯이 자기 어드미턴스와 상호결합에 의한 영향을 받기 때문에 원하는 방사패턴을 얻기 위해서는 상호 어드미턴스를 고려하여 슬롯의 길이와 오프셋을 고려하여야 한다. 슬롯에서의 전계분포 해석은 모멘트법(method of moment)을 사용하여 해석하였다. 본 연구에서는 직선편파특성을 가지는 슬롯 배열 안테나의 설계를 위하여 슬롯의 자기 및 상호 어드미턴스를 구하고, 반복적인 수치해석 과정을 통하여 입력임피던스의 최적화 방법에 대하여 논하였다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.7
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• pp.99-110
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• 1996

In this paper, the analysis o fthe electric field distribution for TEM cell which is matched iwth 50 is performed, and the relations of variables for characteristic impedance are derived. Quasi-static approximations are used to calculate the fiedl strength of the internal field of TEM cell. The results of the improved method for analysis of the electric field is compared with that of R.J. Spigel. and the improved method for characteristic impedance and the results of numerical analysis are shown.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.11-21
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• 2000

을 합하여 얻을 수 있다. 이와 같은 광선 추적법을 적용한 해석적 방법은 디지털 방송의 수신 영역을 결정하는 중요한 두 요소인 수신 전계강도 및 다중 경로 간섭을 비교적 정확히 예측할 수 있다. 개발된 모델을 이용하여 디지털 방송 환경에서 동일채널 중계기로 인한 방송 수신 영역의 확대 또는 축소를 예측할 수 있으며, 중계기의 최적화 위치를 찾는 데 활용할 수 있다.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.3-6
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• 1990

The impact of the convected charges, which is caused by the electrification phenomina, in the oil-paper insulation systems of power transformers has been numerically investigated using FEM. The potential distribution of the oil-paper insulation system is assumed to be governed by three equations instead of the classical Laplace equation. When the charge density of oil and the conduction current are kept high, the field distortion or the interrace in a power transformer is considerably distorted due to the convected charges.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.399-402
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• 2001

In this paper, 3-dimensional charge simulation method was applied to analyze electric field distributions of special conductor bundles equipped with spiral rods for reducing aeolian noise in a corona cage. Comparing electric field distributions of special conductor bundles in 765kV transmission tine with ones in corona case, we decide experimental voltages of special conductor bundles in corona cage.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.528-530
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• 2000

In this paper, electric field distribution of GIS by changing conductivity of spacer is analysed by the use of 3 dimensional Surface Charge Method. We find electric field distribution inside GIS was much influenced when volume resistance are lower than $10^7[\Omega-cm]$.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.359-361
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• 2001

In this paper, 3-dimensional charge simulation method was applied to analyze electric field distributions of special conductor bundles equipped with spiral rods for reducing aeolian noise in a corona cage. We found calculation error of this method was w a reasonable boundary of 0.5%.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2117-2119
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• 1999

In this paper, the electric fields inside GIS with metal impurity is analysed by the use of 3 dimensional Surface Charge Method. We find the metal impurity makes electric field distribution inside GIS non-uniform and causes breakdown of $SF_6$ gas in GIS.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1987-1989
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• 2000

In this paper, electric field distribution of dielectric sphere considering surface or volume resistivity is analysed by the use of rotational symmetric charge simulation method. We applied three methods such as ${\alpha},{\beta}$ modified $\beta$ method to check electric field calculation error. We find f method and modified $\beta$ method are suitable to simulate volume and surface resistivity respectively.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.75-81
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• 2000

This paper describes the partial discharge due to particles in $SF_6$ gas. A model GIS chamber was designed and manufactured. The partial discharge and breakdown phenomena due to the particles between electrodes were observed and partial discharge signals were detected, using an ultrasonic sensor. The analysis of the electric field by the states of the particle inserted between the electrodes, were also carried out. The partial discharge was observed at end while the particle was moving in $SF_6$ gas. The partial discharge in micro-gap grows to arc, and after all, it can cause a breakdown.The electric field strength was the highest in case that the particle was vertically attached on the conductor, and the lowest in case that it was horizontally attached on the enclosure.