• 한국전기전자재료학회논문지
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• 제21권10호
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• pp.950-953
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• 2008

YBCO coated conductor called the second-generation superconducting tapes have resistance increase significantly more than BSCCO tapes in terms of the speed or amount when quench occurs, they may have different ranges of application. Such characteristics are thought to get different properties by selection of stabilizing materials in manufacturing superconducting tapes. It is important in selecting superconducting tapes which will be applied to power devices in the future. In this study, one kind of BSCCO tapes and two kinds of YBCO CC with different stabilizing materials and one kind of YBCO CC with non stabilizing materials were used to compare and examine transport characteristics in flux-flow state and quench state with each tape joint of HTS tapes.

• Transactions on Electrical and Electronic Materials
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• 제10권2호
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• pp.62-65
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• 2009

YBCO-coated conductors, called "second-generation wires," show a remarkably greater increase in the amount or speed of their resistance than BSCCO wires when a quench occurs. This is probably because of the specific resistance at their stabilizer layer, which also affects their voltage grade. YBCO coated conductors with copper as a stabilizer layer have a voltage grade of 1.5-2 V/cm, and those with stainless steel as a stabilizer layer have a voltage grade of about 0.5-0.6 V/cm. The voltage grade of YBCO coated conductors is important in selecting and applying superconducting wires to power instruments later. In this study, two kinds of YBCO-coated conductors with different stabilizer layers and one kind of BSCCO wire were prepared. Among them, based on the YBCO coated conductors that had a stainless steel stabilizer layer with a low voltage grade, five kinds of experimental samples for joining were prepared with the remaining two kinds of wires. Using the prepared samples, the current application properties and the resistance increase in the flux-flow and the quench states of the single wire and the joined wires were compared.

• 한국전기전자재료학회논문지
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• 제14권6호
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• pp.518-524
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• 2001

We report the current limiting properties of superconducting fault current limiters (SFCL). Our SFCL was patterned in a spiral type on a YB $a_2$C $u_3$$O_{7-x}$(YBCO) film deposited using rf sputtering techniques and was coated with a gold shunt layer in order to disperse the heat generated at hot spots in the YBCO film. Current increased up to 13.5 $A_{peak}$ at 60 Hz for the voltage of 13 $V_{peak}$, which is the minimum quench point, and increased up to 17.6 $A_{peak}$ at 60 Hz fo the voltage fo 141.4 $V_{peak}$. The quench completion time was 5 msec at 13 $V_{peak}$ and 4 msec at 141. $V_{peak}$ respectively. we think that this architecture using spiral-type SFCL can be useful for the protection of the power delivery systems from fault currents.s. currents.s.

• 대한전기학회논문지:전력기술부문A
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• 제49권8호
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• pp.418-423
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• 2000

In this paper, we reported the current limiting properties of superconducting fault current limiters (SFCL). Our SFCL was patterned in a coil-type on a YBCO film deposited using rf sputtering techniques and was coated with a gold shunt layer in order to disperse the heat generated at hot spots in the YBCO film. Current increased up to 13.5 Apeak at 60 Hz for the voltage of 11.5 Vpeak, which is the minimum quench point, and increased up to 17.6 Apeak at 60 Hz for the voltage of 80 Vpeak. The quench completion time was 5 msec at 11.5 Vpeak and 4 msec at 80 Vpeak respectively. We think that this architecture using coil-type SFCL can be useful for the protection of the power delivery systems from fault currents.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.169-172
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• 2004

We present the basic properties of a superconducting current limiting fuse (SCLF) based on YBCO/Au films. The SCLFs consists of YBCO stripes covered with Au layers for current shunt. Under the source voltage of 100 $V_{rms}$, the longer the duration time of fault current was, the shorter its discharge time was. The duration time of fault current and its discharge time were reduced by increased voltages in the range of 200 - 300 $V_{rms}$. We thought that this was because the quench propagation was limited by local melting generated with higher voltage.

• Archives of Pharmacal Research
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• 제6권1호
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• pp.63-68
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• 1983

The binding properties of three ginsenosides, Rb$_{1}$, Rc and Re, to bovine and human serum albumins have been examined by fluorescence probe technique. 1-anilinonphathalene-8-sulfonate (ANS) was used as the fluorescence probe. Protopanaxatriol glycoside, Re, did not quench the fluorscence of ANS to the bovine serum albumin. Competitive bindings between protopanaxadiol glycosides, Rb$_{1}$ and Rc are both 3.3 . The binding constants for Rb$_{1}$ and Rc with bovine serum albumin were 1.91 * 10$_{4}$M$_{-1}$ AND 1.04 * 10$^{[-994]}$ M$^{-1}$ , respectively. The ginsenosides, Rb$_{1}$, Rc and Re did not quench the fluorescence of ANS bound to human serum albumin.

• 한국분말재료학회지
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• 제22권1호
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• pp.10-14
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• 2015

In recent years, industrial demands for superior mechanical properties of powder metallurgy steel components with low cost are rapidly growing. Sinter hardening that combines sintering and heat treatment in continuous one step is cost-effective. The cooling rate during the sinter hardening process dominates material microstructures, which finally determine the mechanical properties of the parts. This research establishes a numerical model of the relation between various cooling rates and microstructures in a sinter hardenable material. The evolution of a martensitic phase in the treated microstructure during end quench tests using various cooling media of water, oil, and air is predicted from the cooling rate, which is influenced by cooling conditions, using the finite element method simulations. The effects of the cooling condition on the microstructure of the sinter hardening material are found. The obtained limiting size of the sinter hardening part is helpful to design complicate shaped components.

• 한국초전도ㆍ저온공학회논문지
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• 제7권1호
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• pp.32-36
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• 2005

With the successful commercialization of Bi-2223 powder-in-tube wire , various attempts in the R & D of the high-Tc superconducting (HTS) magnets for high magnetic field applications are being implemented actively. Operating temperature of HTS magnet has to be maintained at the designed level but the magnetic energy and mechanical disturbance can cause unstable operational temperature of HTS magnet. Especially the generated heat energy of inner HTS winding Is apt to be accumulated . so the normal region appears in HTS winding. This paper deals with the quenching characteristics of three kinds of selected Bi-2223 wires : the High Current Density Wire (HC-A) and the High Strength Wire (HS-A) made by AMSC and HTS wire(HW-I) made by Innost The Innost wire has the highest minimum quench energy (MQE). The High Current Density Wire has the highest normal zone Propagation velocity (NZPV).

• 전기학회논문지P
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• 제57권3호
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• pp.323-327
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• 2008

We investigated the quench characteristics of a flux-lock type superconducting fault current limiter (SFCL) depending on the methods of the serial and parallel connections between the superconducting elements. The flux-lock type SFCL consists of two coils. The primary coil is wound in parallel to the secondary coil through an iron core, and the secondary coil is connected to the superconducting elements in series and parallel. In this paper, the analyses of voltage, current, and resistance of the superconducting elements connected in serial and parallel were performed to increase the power capacity of the flux-lock type SFCL. A part of the superconducting elements was not quenched in $2{\times}2$ serial connection between the elements and then the power burden of the quenched elements was increased. However the elements with $2{\times}2$ parallel connection was all quenched. This means that the power burden of each superconducting element can be reduced under the same conditions. We found that $2{\times}2$ parallel connection was more profitable for the current limiting effects and the increase of the power capacity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.663-665
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• 2000

We fabricated resistive superconducting fault current limiters (SFCL) based on YBCO thin films grown on 2-inch diameter saphire substrates Two SFCLs with nearly identical properties were connected in series to investigate the simultaneous quench. There was a slight difference in the rate of voltage increase between two SFCL units when they were operated independently. This difference. however, resulted in significantly unbalanced power dissipation between the units. This imbalance was removed by connecting a shunt resistor to an SFCL in parallel. The appropriate values of the shunt resistances were $80{\Omega}$ at $75 V_{rms}$. $100{\Omega}$ at $100 V_{rms}$ and $110{\Omega}$ at $120 V_{rms}$, respectively. Increased power input at high voltages also reduced the initial imbalance in power dissipation. but with increase in film temperature to higher than 200 K.