• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.213-215
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• 2001

This paper describes an improved analysis method for sheath circulating current on three-underground transmission cables using EMTP(Electromagnetic Transient Program). Author studied diversely the sheath circulating current on three-underground cables depending on the various length rate, the phase arrangement, and the grounding resistance of the sheath in the cross-bonded section. It was clear that very large circulating current is generated in cable systems due to unbalanced length rate and phase arrangement in the cross-bonded section. The analysing method for two or more underground cables will be really Improved for cable system utility.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.40-43
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• 2001

In order for the World cup football game to be operated stably with duplicate service electric power supply, It is done, emergency generator and the U.P.S it establishes. the electric power system power control, lighting control, integrated monitoring. rue fighting. obstruction light, the searchlight, snow melting, electric erosion shield. grounding, the lightening protection and viewable lighting, stadium floodlight and an electric bulletin board it composed of the back which it sells.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.8
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• pp.1262-1268
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• 2015

I In power transmission systems, voltage changes continuously as reactive power is whether over supply or shortage. Reactive power produces in generators and consumes in transmission lines, and loads. Voltages at end points of transmission lines rise which is called Ferranti effect. Excessive voltage rising can reduce transmission equipment life, the voltage rising is usually permitted within the limit of 10%~30% excess. Shunt reactors are installed in transmission lines to put a curb on voltage rising. In this paper, we tried to do modelling for shunt reactor configuration types which are no grounding, grounded and grouded neutral reactor. Simulation are carried out for reactor magnitude for compensating transmission line capacitance.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.468-470
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• 1999

Using the EMTP(Electro Magnetic Transient Program) for the analysis of lightning direct voltage on the railway system, the shielding effects of overhead grounding wire on the railway were studied quantitatively. Installation of overhead ground wire and sap-type arrester such as s-horn provides a 6.6kV HV distribution line with goof protection effects. Even severe lightning induced voltage were create, 6.6kV HV lines can be withstand.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2207-2209
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• 2000

본 논문에서는 접지 모델을 활용하여 접지계의 임펄스 임피던스를 계산하고, 선로 임피던스에 연결된 접지 임피던스의 반사계수를 계산하여 대지로 유입되는 분류율을 평가하였다. 따라서 접지 저항을 낮추는 경우 평상시 전위 상승효과를 줄일 수는 있지만 위험전압의 인가시에는 인축의 안전과 기기의 절연 측면에서 악조건의 상황이 될 수 있다. 또한 접지 모델에서 용량의 변화와 접지 저항의 변화에 따른 반사계수의 변화를 확인하였고, 상용 주파수 근처에서는 저항 성분만 존재하고 리액턴스 효과는 없음을 확인하였다.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.9-14
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• 2007

In this paper, four types of igniters were modeled and their characteristics were researched. And then we analyzed and experimented the effect on the control IC operation in this system. Due to the high ignition voltage, the DC power line on control IC is contaminated with the impulsive noise voltage. So the control IC operation is stopped. Therefore we have found that contamination of DC power noise is reduced by shielding, grounding pattern, and filtering method. We showed that the experimental results are agreed with the theoritical value obtained by the four types of ignitor models.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.4
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• pp.193-200
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• 2003

The use of underground transmission tables has continuously increased in densely inhabited urban and suburban area. Due to a increasing demand of underground cables, two or more circuits are installed in parallel for several kilometers. It, however, has not been realized that the sheath circulating current is generated in the system where a large number of cables are laid in the same route. In this paper, Author studied diversely the sheath circulating current on underground cables depending on the various length rate, the phase arrangement, and the grounding resistance of the sheath in the cross-bonded section. It was clear that very large circulating current is generated in cable systems due to unbalanced length rate and phase arrangement in the cross-bonded section.

• Proceedings of the KIEE Conference
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• 2007.04b
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• pp.5-9
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• 2007

본 논문에서는 실제 운용 중인 현장에서 노이즈 및 서지 신호를 측정 분석하여, 그 결과를 토대로 이들 노이즈 신호를 제거할 수 있는 접지시스템 및 내부 보호 설비를 제안하여 시공하였다. 실제 운용 중인 설비 내에 유도 흑은 침입하는 전원 계통의 sag, Swell, Transient, 서지 그리고 고조파와 같은 노이즈와 접지시스템을 통해 유입되는 다양한 노이즈 신호를 차단하여 빠르고 안전하게 제거하는 방안을 연구하였다. 이를 위해 운용 중인 설비의 다양한 노이즈 신호를 실측하였고, 실측된 결과로부터 전달 및 침입 경로를 예측하여, 기존 접지 구성 및 내부 배선의 문제점의 개선하고 노이즈 및 서지의 실제적 차단을 위한 접지시스템과 내부 보호 설비를 설계 제안하였다. 또한 설계 시뮬레이션 결과와 현장 시공 결과를 비교하여 제안된 설비의 성능을 확인하였고, 시공 후 설비 운용 중에 노이즈 및 서지 신호를 재 측정하여 기존 설비 운용시 측정했던 결과를 비교 분석하여 제안 보호 설비의 개선된 성능을 최종 확인하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.95-99
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• 2004

A systematic approach of measurement, modeling and analysis of grounding system impedance in the field of lightning protection systems is presented. The measurement and analysis of ground impedance are based on a computer aided technique. The magnitude and phase of ground impedance were measured and analyzed by the modified fall-of-potential method and the proposed computer program algerian using the waveforms of the test current and potential rise. The theoretical analysis of ground impedance were performed with the equivalent circuit models, and the theoretical results were compared with the measured data.

• Journal of the Korean Society of Safety
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• v.27 no.6
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• pp.43-47
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• 2012

The unbalance currents flow the High Temperature Superconducting (HTS) power cable caused by asymmetrical fault, harmonic distortion and unbalanced load. That problem causes additional loss and leakage field in the HTS power cable, and deteriorates the electric power quality and stability. In addition, large amounts of unbalanced current can cause negative sequence and ground relays to operate. This paper presents an analysis unbalanced three-phase current distribution in HTS power cable caused by unbalanced load condition and grounding methods using PSCAD/EMTDC. The results obtained through the analysis would provide important data for the design of HTS power cables and valid information for their installation in power system.