• Structural Engineering and Mechanics
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• 제50권1호
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• pp.37-52
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• 2014

The accurate determination of cable tension is important to the monitoring of the condition of a cable-stayed bridge. When applying a vibration-based formula to identify the tension of a real cable under sag, stiffness and boundary conditions, the resulting error must not be overlooked. In this work, by resolving the implicit frequency function of a real cable under the above conditions numerically, indirect methods of determining the cable force and a method to calculate the corresponding cable mode frequency are investigated. The error in the tension is studied by numerical simulation, and an empirical error correction formula is presented by fitting the relationship between the cable force error and cable parameters ${\lambda}^2$ and ${\xi}$. A case study on two real cables of the Shanghai Changjiang Bridge shows that employing the method proposed in this paper can increase the accuracy of the determined cable force and reduce the computing time relative to the time required for the finite element model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.424-429
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• 2003

As a critical member of cable-stayed bridges, stay cables play an important role of supporting the entire structure. Traffic, wind or rain-wind induced vibrations of stay cables would be a major cause of degrading both safety and serviceability of the bridge. One of the effective alternatives to solve this problem is to employ the cable dampers. In order to design the cable damper optimally. it is necessary to exactly estimate the dynamic characteristics of the existing cables. Therefore, in this study, a cable exciting system (exciter) controlled digitally was developed. And to evaluate the performance of the cable exciter developed, a solution of the differential equation of cable motion considering the exciter was derived. Using the cable exciter. sine sweeping and resonance tests on a cable model were carried out to obtain the dynamic characteristics effectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1134-1136
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• 1998

In case of multi-cable for one ph current in the same phase cable may be unba according to cable arrangement in underg system. In this paper, we described the way to ba current in each cable of same phase. This solut to make the impedence of each cable equal caculated the impedence of each cable for all ki cable arrangement in accordance with JCS168D finally found the cable arrangement of impedence.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.198-199
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• 2007

The Cable Transit has an adaptable center hole for accommodating a cable to be passed through the wall(bulkhead/deck). The Cable Transits Sealing System must have important character which seal and protect against fire, smoke, gas, water, etc and consist of natal frame, sealing system and the cable, insulation. In this paper, introduced our cable transit organic expansion sealing material system, fire-resistance test and test result, etc. We carry to fire-resistance test in according to FTP Code Part 3(IMO Res. A. 754(18)) for A-60 class cable transit and the test result for our cable transit sealing system was satisfied.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.192-192
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• 2010

DAPAS (Development of Advanced Power system by Applied Superconductivity technologies) program that the, superconductivity national program has been started one of the 21C frontier programs from 2001 in Korea. The 3rd phase of DAPAS program was started at April 2007, and the ultimate goal of HTS cable project is to develop 154kV, 1GVA class HTS cable. The structure of 154kV, 1GVA HTS cable is single core with cold dielectric insulation. The cable core consists of the former, conduction layer, electrical insulation layer, shielding layer. The cable cryostat consists of two corrugated seamless aluminum tubes as its high sealing reliability, the tubes separated through a spacer arrangement. Outdoor termination was developed by LS cable and cryogenic system by CVE for 154kV, 1GVA class HTS cable. The 154kV, 1GVA HTS cable will be installed and be tested in KEPCO Gochang Testing Center from June 2010.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.224-228
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• 1988

Extensive development work which was carried out by Gold Star Cable Co., Ltd. has led to the optimal design, manufacture and test of fully engineered cable system for 345 kV self- contained oil filled (OF) underground cable. Details of design criteria and of tests are given. development of 345kV OF cable results in sucessful operations for ultra-high voltage power transmission requirement.

• 한국전산구조공학회논문집
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• 제20권1호
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• pp.1-7
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• 2007

본 연구에서는 케이블구조의 초기형상해석을 위한 새로운 탄성포물선 케이블요소(elastic parabolic cable element)를 제시한다. 이를 위하여 먼저 탄성현수선 케이블요소(elastic catenary cable element)에 대한 적합조건과 접선강도행렬 유도과정을 간략히 한다. 이를 토대로 장력이 충분히 도입되어 자중에 의한 처짐 형상이 포물선에 가깝다는 가정 하에서 무응력길이를 포함하는 탄성포물선 케이블요소의 비선형 힘-변형관계식과 접선강도행렬을 유도한다. 또한 현(chord) 방향으로 두 케이블요소의 등가 장력식을 정의한다. 본 요소의 정확성을 확인하기 위하여, 탄성현수선과 탄성포물선 케이블요소를 각각 적용하여 고정하중을 받는 사장교의 초기형상해석을 수행하고 무응력길이, 등가장력, 그리고 최대장력 결과를 비교, 분석한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.616-618
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• 2007

This paper describes the mechanical and electrical test on HVDC submarine cable, Flexible Repair Joint and termination for 180kV. This HVDC submarine cable was manufactured using LS cable's unique skill and would be applied the HVDC submarine cable system in korea. The performance test consist of mechanical test and electrical test. The tensile bending test and tensile test was done as the mechanical test and Electrical test is DC voltage and Impulse test. The tensile bending test carried out 6 times(double of specified times) for maximum reliability. The DC test voltage is $\pm$400kV/1hr. We estimate the lower limit of DC breakdown voltage is 600kV. The impulse test voltage is $\pm$800kV/10shots. The type of developed cables is the MI type. Its insulation consist of paper tapes impregnated with a high viscosity oil. The development of new HVDC cable is available for HVDC underground or submarine power transmission. The developed HVDC cable, FRJ and termination have passed the mechanical and electrical test successfully and showed excellent performance.

• Structural Engineering and Mechanics
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• 제23권6호
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• pp.691-711
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• 2006

This paper uses the finite element method to simultaneously consider the coupled cable-deck vibrations and the parametric vibrations of stay cables in dynamic analysis of a cable-stayed bridge. The stay cables are represented by some cable finite elements, which can consider the parametric vibration of the cables. In addition to modeling stay cables using multiple link cable elements, a procedure for removing the self-weight term of cable element is proposed. A eigenvalue analysis process using dynamic condensation method for sorting out the natural modes of the girder-tower vibrations and the Rayleigh damping considering element damping for damping matrix are also proposed for dynamic analyses of cable-stayed bridges. The possibilities of using cable elements and of using global and local vibrations to evaluate the parametric vibrations of stay cables in a cable-stayed bridge are confirmed, respectively.

• 한국정보통신학회논문지
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• 제20권3호
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• pp.607-614
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• 2016

발전소 설비에서 케이블 포설을 위한 설계는 발전소 설비에 사용되어지는 케이블 유형의 다양한 형태로 인해 매우 많은 시간이 요구되고 매우 중요한 과제이다. 케이블 포설 설계 시 레이스웨이(Raceway)는 출발지(Source) 장비로부터 목적지(Destination) 장비까지의 케이블 트레이(Tray) 및 콘디트(Conduit)의 포설 구간을 의미한다. 기존의 케이블 포설 설계 과정은 모두 수기에 의해 작성되어 인적/시간적 투자손실이 크고, 케이블의 누락 및 케이블 오버필(Over Fill)과 같은 비효율적인 손실이 빈번히 발생한다. 따라서 본 논문에서는 효과적인 발전소 케이블 포설 설계를 위한 레이스웨이의 유연한 케이블 오버 필(Fill) 체크 기반의 자동화된 케이블 라우팅 경로 계산 알고리즘을 구현하였고, 제안한 자동화 케이블 라우팅 설계기법은 케이블 위치의 변화에도 유연한 레이스웨이 계산이 가능하다. 구현 결과, 케이블 라우팅 설계 프로그램은 발전소 케이블 포설 설계 사양을 준수하면서 케이블 라우팅 경로를 효과적으로 설정하고, 케이블 포설 설계 시간을 기존 대비 크게 단축하는 성능을 얻을 수 있었다.