• 한국초전도ㆍ저온공학회논문지
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• 제12권1호
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• pp.37-41
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• 2010

To limit fault current in a power system, superconducting fault current limiters (SFCLs) using high temperature superconducting (HTS) coils have been developed by many research groups so far. Non-inductive winding of HTS coils used for SFCLs can be classified into solenoid winding and pancake winding. Each of winding is expected to have different quench and recovery characteristics because the structure of solenoid winding differs from pancake winding's. Therefore it is important to the SFCLs application to investigate characteristics of each winding. In this paper, we deal with quench and recovery characteristics of four kinds of winding : solenoid winding, pancake winding without spacers, and with spacers of 2 and 4 mm thickness. In order to obtain quench and recovery parameters of coils, short circuit tests were performed in liquid nitrogen.

• 조명전기설비학회논문지
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• 제25권9호
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• pp.75-79
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• 2011

The MOV(Metal Oxide Varistor), a voltage limiting element, has been installed in the SPD(Surge Protective Device) or inside the internal circuit of an electronic appliance for protection of the electric power system and electronic device against electrical surge. Such an MOV is exposed, however, to the risk of the thermal runaway resulting from excessive voltage and deterioration. In this paper, a reciprocal action has been tested and analyzed using a phosphorus bronze switching module and the low-temperature solder. And a short current break characteristic test linked with the circuit breaker has been performed to limit the inrush current when the MOV breaks down. It has been proven that the phosphorus bronze switching module installed inside the internal circuit can improve the safety of the power line system and the electronic device.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1041-1042
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• 2011

저압 차단기의 단락성능평가를 위한 단락시험설비의 측정시스템은 고전압, 대전류를 안전하고 정밀하게 측정하기 위해 여러 가지 측정기들로 시스템으로 구성되어 있으며, 시험 신뢰도의 확보를 위해 측정불확도에 대한 평가가 이루어져야 한다. 본 논문에서는 표준 Shunt와 비교시험을 통하여 전류 측정 시스템의 측정불확도를 추정하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 합동춘계학술대회 논문집 전기물성,응용부문
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• pp.133-134
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• 2008

This paper describes a testing method to assess the reliability of the epoxy bushing used for the vacuum circuit breaker(VCB). Especially, in order to show the long-term durability of epoxy bushing in a short testing duration, the extremely accelerated electric stress applying test plan was adopted.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.882-885
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• 2001

This paper aims to investigate the characteristics of braided thermoplastic composite and pressure relief for polymer arrester. In general, braided composite has potential for improved impact and delamination resistance. Manufacturing processes of the braided composite could also be automated and could potentially lead to lower costs. Therefore, in consideration of characteristics of pressure relief for polymer arrester, the fabric pattern of braided composite was decided. And polymer arrester module was manufactured with braid.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.455-458
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• 2001

This paper presents an axial flux permanent magnet synchronous generator with a high power-to-weight ratio, dedicated for small-scale gearless wind power generation plants. For this purpose, a specific design is necessary to meet the imposed requirements. In this paper the design technique for the specifications is presented. The aim of the paper is also to discuss some of the first obtained test results and the involved demagnetizing problem (i.e. short-circuit).

• 전자공학회논문지A
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• 제33A권3호
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• pp.176-186
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• 1996

As the density of VLSI increases, the conventional logic testing is not sufficient to completely detect the new faults generated in design and fabrication processing. Recently, IDDQ testing becomes very attractive since it can overcome the limitations of logic testing. In this paper, G-ATPG (gyeongsang automatic test pattern genrator) is designed which is able to be adapted to IDDQ testing for combinational CMOS VLSI. In G-ATPG, stuck-at, transistor stuck-on, GOS (gate oxide short)or bridging faults which can occur within priitive gate or XOR is modelled to primitive fault patterns and the concept of a fault-sensitizing gate is used to simulate only gates that need to sensitize the faulty gate because IDDQ test does not require the process of fault propagation. Primitive fault patterns are graded to reduce CPU time for the gates in a circuit whenever a test pattern is generated. the simulation results in bench mark circuits show that CPU time and fault coverage are enhanced more than the conventional ATPG using IDDQ test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.220-220
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• 2009

We are developing of the evaluation technique and system for testing the performance of circuit breaker using Simplified Synthetic circuit. This facility specification is up to 90[kApeak] and up to 300[kVpeak]. It is possible to verify the interrupting capability by using low-energy and reduce the development period and the cost.

• 제어로봇시스템학회논문지
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• 제17권2호
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• pp.171-175
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• 2011

In this paper, I have developed a high-speed and high-resolution measuring device in order to check the performance of drycell. The system is developed for the drycell manufacturing plant. Measuring time is one of key factors to inference on the production speed. So the developed system is designed to generate the classified result up to 1200ea/min. In the other words, each product can be classified within 25ms. There have been many studies to estimate both state of charge as well as state of health, such as OCV (Open Circuit Voltage), SC (Short Circuit) and measuring impedance with frequency pulse. But those methods take a few second due to surface discharge. To overcome the phenomenon, I developed the method to engage the reverse current to two electrodes of battery. As a result, I could achieve to measure the indigenous capacity without the problem of surface discharge.

• 한국초전도ㆍ저온공학회논문지
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• 제9권1호
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• pp.9-13
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• 2007

Coated conductor(CC) is recently in actively progress for the research and development, and its can be used various stabilizer lot the specific requirements for each application. Among various superconducting applications, coated conductor applied to superconducting fault current limiters(SFCLS) bypasses fault current to its stabilizer, where the surge is abruptly reduced ; thus, stainless steel, which has large resistivity can be a suitable stabilizer for SFCLS. Despite high n-value of the YBCO, CC stabilized with stainless steel did not effectively limit the first peak fault current. In the short circuit test results of AMSC's 344S, a half period delay was observed between the fault and the generation of resistance(60Hz). In this paper, we performed short-circuit experiments with stacked and unstacked CC and compared the test results to analyze effective fault current limiting characteristics. we compared time of the generated resistance as the fault current limiting characteristics and made the samples one is the stacked CC and the other is unstacked CC. These samples were used equal numbers of pieces of CC. In addition, comparison and analysis was made for the stacked structure by measuring fault current limiting characteristics with respect to thermal insulation by impregnating with epoxy resin.