• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.33-38
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• 2007

This paper presents a experimental evidence of the generation of the earth potential and communication line noise from the electric railway. There is a critical measurement err in case of measuring the electrical power induced noise voltage and degree of cable balance in the field of earth potential generated. As a results, it has been found that the conventional cable has more noise immunity than shielded cable near the railway where the earth current flows through the sheath layer.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.736-737
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• 2007

The single point bonding in underground transmission system can induce high voltage on the sheath when ground fault, lightning serge and switching serge occurs, at that time underground cable systems cannot offer a return path of fault current. Accordingly if fault current, which cannot return to ground, flows at the single point bonding, high voltage can be induced in SVL and that voltage can cause aging and breakdown of SVL. Therefore this paper study on the effect of parallel ground conductor at the single point bonding when ground fault and lightning serge occurs by using ATPDraw.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.470-471
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• 2008

SVL is installed at underground transmission system to protect cables and insulation joint-box from overvoltages caused by lightning, switching, and line-to-ground fault. Domestic underground power system adopts cross bonding type to reduce the induced voltage at sheath, but single-point bonding is required depending the system installation configuration. SVL can be easily broken by overvoltages induced at joint-box because single-point bonding has uneffective system structure to extract fault current. ANSI/IEEE recommends Parallel Ground Continuity Conductor(PGCC) to prevent SVL breakdown. In this paper, EMTP simulation is performed to analyze effects on SVL under PGCC installation when single-line-to-ground fault occurs. The result shows that PGCC and short single-point bonding distance can reduce overvoltages at SVL.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.10
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• pp.181-189
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• 2007

This paper presents a experimental evidence of the generation of the earth potential and communication line noise from the electric railway. There is a critical measurement err in case of measuring the electrical power induced noise voltage and degree of cable balance in the field of earth potential generated. As a results, it has been found that the conventional cable has more noise immunity than shielded cable near the railway where the earth current flows through the sheath layer.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.9
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• pp.1689-1694
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• 2009

In a previous paper, the characteristics of ECC (earth continuity conductor) have been analysed for reducing the level of induced sheath voltage considering the dimension and position of ECC, the spacing between ECC and three phase cables, and the use of two ECC conductors at the single point boned section of underground power cable system. From these results, the study conditions for optimal installation has been selected such as installation section, conductor size and etc. In this paper, 5 cases which are set by possible installation conditions are tested based on previous research results. Finally, the optimal installation method of ECC is selected on underground power cable systems.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.2
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• pp.102-108
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• 2002

This paper describes the overvoltage analysis and reduction methods of insulation joint boxes in underground transmission power cables when direct lightning surge strikes to overhead transmission line. An actual 154kV combined transmission line with underground Power cables was modelled in ATPDraw for simulation. Simulations were performed to analyze the overvoltage between insulation joint boxes, sheath-to-ground voltage according to the distance between cable conductors, cable lengths, burying types, CCPU connection types. The most effective method to reduce the induced overvoltage of Insulation joint boxes was proposed. It is evaluated that the proposed reduction method riven from the detailed simulations can be effectively applied to the actual underground power cable systems.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.2
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• pp.85-93
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• 2008

In 22.9[kV]-y distribution systems, underground cables are provided with 3-wire loop multiple-point ground in which each coaxial-neutral line of the distribution cable lines(A, B, C phases) is 3-wire common grounded at every connecting section. In the underground cable distribution systems, circulating current flows in the coaxial-neutral lines and its magnitude amounts to about $40{\sim}50[%]$ load currents, even though loads are balanced. This paper presents a new ground method to overcome such a problem and a comprehensive analysis in tows of current capacity of power cables, induced voltage of cable sheath, and electromagnetic interference voltage from power cable lines.