• 대한전기학회논문지:전력기술부문A
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• 제49권1호
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• pp.19-25
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• 2000

This paper describes the sheath induced voltage in underground transmission cable system which will be operated with cable cover protection unit(CCPU). Simulation was carried out to analyze the sheath induced voltage in the real cable system which was installed by 154㎸ CV cable in the case with and without CCPU. The sheath induced voltage will be also analyzed according to the change of grounding method, fault resistance and fault angle. Simulation was performed using EMTP and ATP Draw, the simulation results show whether the CCPU in necessary or not in underground transmission power cable system.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.285-288
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• 2007

This article presents the change characteristics of induced noise whether the sheath layer of the cable is grounded or not. As what affects the induced noise, there are power influence or longitudinal transverse voltages and its weighted filtered voltage. The sheath ground is basicaly predicted to have the effects of alleviation on the power influence. But practically the effects may not happen in the case of common cable's sheath layer. Rather there are cases that the ground of sheath affects so that the noise level could increase. So we need to scrutinize the effects of the sheath gorund in the measures for the protection against electromagnetic induction by powerline or traction line system. And the evaluation of using the designated shielding purpose cable is needed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1179-1181
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• 1998

This paper describes the induced voltage of sheath on 154kV transmission power cable in multi fault states. Simulation was carried out to obtain the induced voltage of sheath according to change of, fault angle and grounding resistance using EMTP. Modeling of cable system is also established in EMTP to analyze. The simulation results can be useful reference to design cable system in power system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1391-1393
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• 1999

This paper have analyzed sheath induced voltage in underground transmission cable system which will be operated with cable cover protection unit(CCPU). Simulation was carried out to analyze sheath induced voltage using on real cable system in the case with and without CCPU. Sheath induced voltage was also analyzed according to grounding method, fault resistance and fault angle. Simulation was performed using EMTP and ATP Draw, the simulation results represent whether the arrester is necessary or not in cable system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.494-496
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• 2001

This paper describes sheath induced voltage and operating characteristic of cable cover protection unit(CCPU) in underground transmission cable. Real cable system operating by 154kV XLPE cable was modelled for simulation. Sheath induced voltage and operating characteristic of CCPU were analyzed. In particular, sheath induced voltage was analyzed in case of individual grounding and common grounding, respectively, and operating characteristics of CCPU were compared each other.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.713-719
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• 2015

통신 회선에 대한 전력선 전자유도 전압을 측정할 때, 일반 통신 케이블의 쉬스 층 및 측정 대상 통신 회선 접지의 상호 접속 관계에 따른 전압 변화를 비교 분석하였다. 케이블 양측 쉬스 접지 저항이 평균 $42.6{\Omega}$으로 유사한 상태에서 쉬스를 분리 접지하고 유도 전압을 측정하면 쉬스 접지를 하지 않은 상태에서 측정한 유도 전압에 대하여 10 % 미만 감소된다. 어느 한 쪽을 공통으로 접지하면 약 50 % 감소되고 양측을 모두 공통으로 하면 90 % 넘게 감소된다. 이것은 국제전기통신연합(ITU)에서 제공하는 계산식으로 계산하였을 때의 결과와 유사한 것으로 분석되었다. 아울러 ITU의 계산식을 활용하여 양측 쉬스 접지 저항 값을 변화시킬 때의 유도 전압 변화를 시뮬레이션하여 비교 분석한 결과, 실제 현장에서 쉬스 접지 저항 기준이 $100{\Omega}$이고 전화 국사의 저항이 보통 $10{\Omega}$ 이하인 점을 감안할 때 측정 오차율은 약 10 % 이하가 된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.93-94
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• 2006

The sheath of a single-conductor cable for ac service acts as a secondary of a transformer, the current in the conductor induces a voltage in the sheath. When the sheaths of single-conductor cables are bonded to each other, as is common practice for multi-conductor cables, the induced voltage causes current to flow in the completed circuit. This current causes losses in the sheath. Various methods of bonding may be used for the purpose of minimizing sheath losses. In korea, sheath cross bonding system was employed for the prevention of sheath losses, the sheaths wire subjected to at voltages, and the bonding was designed to keep the magnitude of the induced voltages within small limits so as to prevent the possibility of sheath corrosion. But, sheath cross bonding system without transposition of cable can not achieve an exact balance of induced sheath voltages unless the cables are lain in trefoil. This paper describes a transposition system with sheath cross bonding using EMTP(Electromagnetic Transient Program). The transposition system with cross bonding can be extended to longer cable circuits for laid in flat as wall as trefoil by the methods described in this paper.

• 대한전기학회논문지:전력기술부문A
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• 제52권12호
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• pp.713-721
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• 2003

This paper analyzes the switching overvoltage occurred on 345kV underground power cable system as well as combined transmission system using EMTP. Cable length and closing time, preinsertion resistance have effect on switching overvoltage. Therefore, this paper analyzes the switching overvoltage occurred on conductor and sheath with change of those parameters. Specially, the cross bonding position becomes discontinuity point because of the difference between surge impedance of metal sheath and that of lead cable. Thus, the transmission and the reflection of traveling wave complexly occur at this connection point. According to these influences, voltage between sheath and earth as well as voltage between joint boxes rise. Time to crest point of switching overvoltage is longer than lightning overvoltage. Even though the voltage induced by switching surge is smaller than lightning surge, that voltage may have serious effect on the metal sheath. Therefore, this paper also analyses the reduction effect of switching overvoltage when the preinsertion resistance of circuit breaker is considered.

• 전기학회논문지
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• 제64권2호
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• pp.240-246
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• 2015

Length of most underground power cable in home is not so long. Therefore it is operated without transposition due to low unbalanced ratio. However, if cable length is long, line constant of each cable will be different. Different line constant can induce unbalanced voltage and current of sheath. Also it can induce several induced interference. This paper describes the effectiveness of transposition through sheath component analysis on transposition and untransposition of cable conductor. Especially sheath current and induced voltage are analyzed and compared in case of transposition and untransposition. EMTP is used for modeling and analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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• pp.156-158
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• 2000

As we are industrialized lately, power capacity is increased in the city urban areas. So the application of underground transmission line is largely expended. In this paper, we analysis the induction voltage on the sheath of 1,200[$mm^2$] OF underground cable being used 154kV underground transmission line. If the current on the cable conductor is 300[A], circulation current is induced the maximum 100[A] on the cable sheath.