Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Progress in Superconductivity and Cryogenics
Journal Basic Information
Journal DOI :
The Korea Institute of Applied Superconductivity and Cryogenics
Editor in Chief :
Hyung-Seop Shin, Won-Nam Kang
Volume & Issues
Volume 10, Issue 4 - Nov 2008
Volume 10, Issue 3 - Sep 2008
Volume 10, Issue 2 - May 2008
Volume 10, Issue 1 - Mar 2008
Selecting the target year
Enhancement of critical current density in
thin Films deposited by TFA-MOD process
Lee, Jong-Beom ; Kim, Byeong-Joo ; Lee, Hee-Gyoun ; Hong, Gye-Won ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 1~5
The effect of
doping on the critical current density of YBCO film by TFA-MOD method was studied.
doping was made by two method; one is direct addition of
nano-sized powder prepared by citrate process followed by grinding with planetary ball mill for 10 hours. Another is addition of Ba-Ce precursor solution prepared with Ba-acetate and Ce acetate dissolved in TFA to the YBCO-TFA precursor solution. The film was made by standard dip coating and heat treatment process with conversion temperature of
in 1000 ppm oxygen containing moisturized Ar gas atmosphere. The direct addition of
powder resulted in YBCO film with good epitaxial growth and no evidence of second phase formation. The addition through precursor solution resulted in the increase of critical current density upto 30 at% doping and uniform dispersion of
fine inclusion was confirmed by SEM-EDX.
High-Ic YBCO thick film fabricated by the MOD process
Shin, Geo-Myung ; Song, Kyu-Jung ; Moon, Seung-Hyun ; Yoo, Sang-Im ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 6~9
We have investigated the MOD process successfully for the fabrication of the YBCO thick film on the
(001) single crystalline substrate. The cracking problem in YBCO thick film, a serious problem in the conventional TFA-MOD method, could be overcome with a careful control of precursor materials. Thus coating solution was prepared for the YBCO thick film by using fluorine-free precursor material. The precursor solutions were coated on the LAO(001) single crystalline substrate using the dip coating method, calcined at the temperature up to
, and fired at various high temperatures for 2 h in a reduced oxygen atmosphere. Optimally processed YBCO thick film exhibited high critical current(
) over 200 A/cm-width at 77K in self-field.
Over-current characteristics of YBCO coated conductors having Cu stabilizer
Yim, S.W. ; Du, H.I. ; Kim, H.R. ; Hyun, O.B. ; Sohn, S.H. ; Lim, J.H. ; Hwang, S.D. ; Oh, S.Y. ; Han, B.S. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 10~14
Differently from BSCCO tapes which are fabricated by powder-in-tube method, the coated conductors are made by the evaporation of YBCO on metal substrate. Due to this structural merit, although the coated conductors are generally used for large current transportation, they are expected to be favorable to the purpose of the fault current limitation as well. In this study, using YBCO coated conductor having copper stabilizer formed by plating technique(produced by Superpower Co.), we investigated the over-current characteristics of the coated conductor. The coated conductors had 85 A
and 90 K
. The resistance of the conductor was 0.93
at 300 K and 0.17
at the temperature right above
. To the coated conductors, we applied the voltages of the range from 150
and measured the V-I curves using four probe method. From the results, we could analyze the electric behavior of the coated conductor in flux flow state. As the current exceed
, the currents were distributed into the superconductor and metal stabilizer. The amounts of the currents shared through both current paths were calculated under the assumption that the ,Joule heating was perfectly eliminated by
surrounding the conductor. Finally, the condition for the stable current flowing state which does not affect the conductor was established from the analysis on the over-current characteristics.
nanodots for the enhanced flux pinning properties in high
Chung, Kook-Chae ; Yoo, Jai-Moo ; Kim, Young-Kuk ; Lee, Hye-Moon ; Wang, X.L. ; Dou, S.X. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 15~18
To achieve high transport current without degradation under magnetic field, it is essential to artificially generate the pinning sites at which moving magnetic flux can be pinned. In this work,
nanodots were formed on the substrate surface using electro-spray deposition method. On top of the nanodots, the extended and effective pinning centers can be created. The positively charged Zr precursor solution was sprayed out from the needle using the corona discharge phenomena. Then, the sprayed precursor was deposited onto the negatively charged substrate surface followed by the heat treatment under the controlled atmosphere. Using the electrostatic force among the charged particles of precursor, evenly distributed and nano-sized dots were formed on the substrate surface. The size and density of the nanodots were studied by Atomic Force Microscopy. Also discussed are the effect of the deposition time and solution concentration on the size and density of the nanodot and processing variables in electro-spray method for the effective flux pinning centers in the superconducting films.
powders by ultrasonic spray pyrolysis
Park, S.C. ; Lim, Y.J. ; Kang, S.G. ; Chung, J.K. ; Kim, C.J. ; Kim, C.J. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 19~23
powders was synthesized with the ultrasonic spray pyrolysis(USP) process using aqueous solutions of boron and magnesium ion. The properties of synthesized
powder were characterized by XRD, SEM and EDS. A small amount of MgO was detected as the secondary phase out of the synthesized powder and the ratios of
to MgO increased with increasing furnace temperature. The particle size and morphology of
powder were investigated with varying molar concentration of the boron and magnesium solution and furnace temperature between
. The average particle size of
showed narrow distribution ranging from 300nm to 400nm. The morphology of particles exhibited mostly spherical shapes and uniform distribution.
Fabrication and fault test of 12 kVA class BSCCO SFCL element
Oh, S.Y. ; Yim, S.W. ; Kim, H.R. ; Hyun, O.B. ; Jang, G.E. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 24~27
For the development of superconducting fault current limiters(SFCLs) having large current capacity, we fabricated an SFCL element that consists of Bi-2212 superconductor and Cu-Ni alloy tubes. First, Ag was plated on the surface of the Bi-2212 for the enhancement of soldering process. On the Ag-plated Bi-2212 tube, a Cu-Ni alloy tube was soldered using optimized solders and soldering conditions. The BSCCO/Cu-Ni composite was processed mechanically to have a helical shape for the improvement of the SFCL characteristics. The total current path of the SFCL element was 1330 mm long with 12 turns, and had critical current of 340 A at 77 K. Finally, we carried out the fault test using the fabricated SFCL element. It showed successful current limiting performance under the fault condition of 50
and 5.5 kA. From the results, the rated voltage of the SFCL element was decided to be 0.4 V/cm, and the power capacity was 12 kVA at 77 K. The fabrication process of the SFCL and the fault test results will be presented.
The study on the DC Ic measurement in the 22.9kV, 50MVA HTS power cable
Choi, S.J. ; Lee, S.J. ; Sim, K.D. ; Cho, J.W. ; Jang, H.M. ; Lee, S.K. ; Sohn, S.H. ; Hwang, S.D. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 28~31
22.9kV 50MVA HTS power cable has been developed and tested by Korea Electrotechnology Research Institute and LS Cable Company and it was supported by a grant from Center for Applied Superconductivity Technology of the 21st Century Frontier R&D Program. In this paper, DC Ic of 100m HTS cable which is installed at Kochang testing station was measured and analyzed. A measurement technique of DC Ic used by resistance and inductance removal method is established.
Current sharing measurement using non-contact method for parallel HTS tapes conductor according to tape array geometry
Byun, S. ; Park, M. ; Choi, S. ; Park, S. ; Lee, S. ; Kim, W. ; Lee, J. ; Choi, K. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 32~36
An HTS conductor with parallel HTS tapes is essential for a large power HTS device to flow a large current. One of the most important factor for this conductor is a current distribution. Non-uniform current distribution in parallel tapes makes the critical current of the conductor low and the AC losses high. In this paper we proposed a non-contact method which measured each current in parallel tapes by using an array of Hall sensors. A matrix can be derived from this array for calibration. The current distributions of 4 and 6 parallel tapes were measured.
Study on the Optimal Design for HTS Magnetic Levitation Magnet
Yoon, Kyung-Yong ; Bae, Duck-Kweon ; Cho, Heung-Je ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 37~41
Superconducting Electrodynamic suspension(EDS) system is generated by the interaction between the magnetic field made by the induced the eddy current in the ground conductor and the moving magnetic field made by onboard superconducting magnet. The levitation force of EDS system, which is proportional to the strength of the moving magnetic field, becomes saturated according to the increase of the velocity. Especially, the levitation force is influenced by the structure of HTS magnet and ground magnet. This paper deals with the optimal design condition for the HTS levitation magnet. The 3-D numerical analysis with FEM was used to find the distribution of the magnetic field, the optimal coil structure, and the calculation of the levitation force.
An Analysis on Current Limiting characteristics of an SFCL using Magnetic Coupling between Two Coils through Computer Simulation
Kim, Jin-Seok ; Ahn, Jae-Min ; Lim, Sung-Hun ; Moon, Jong-Fil ; Kim, Jae-Chul ; Kim, Chul-Hwan ; Hyun, Ok-Bae ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 42~47
In this paper, the fault current limiting characteristics for the superconducting fault current limiter(SFCL) using magnetic coupling between two coils were investigated. The SFCL consists of a high-
superconducting(HTSC) element and two coils. This SFCL has different characteristics that depend on the connection form, the winding direction and the inductance ratio of two coils. The impedance and the operational current of the SFCL can be adjusted higher or lower than the resistance and the critical current of HTSC element. Therefore, the SFCL can change the amplitude of the limited fault current. To confirm it, the HTSC element was modeled and the fault current limiting characteristics of the SFCL were analysed through computer simulation. It was obtained from the analysis that the connection form and the winding direction of two coils of the SFCL were the important design parameters.
The propulsive plan on the standardization in 22.9kV, 50MVA HTS power cable
Choi, S.J. ; Lee, S.J. ; Sim, K.D. ; Cho, J.W. ; Lee, S.K. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 48~51
The standardization on superconducting application techniques has been focused only in testing method or material itself, but, recently, it is actively proceeded by superconducting technical committee(TC) of international electro technical commission(IEC). In this paper, the standardization organization and its necessary process is introduced and the standardization technique for 22.9kV, 50MVA HTS power cable is prescribed. Throughout this research, it is possible to take priorities on the standardization technique in HTS power cable application. And moreover it can also contributes to the commercialization of HTS power cable.
Measurement of AC Loss in SmBCO Coated Conductor
Park, M.J. ; Kim, W.S. ; Lee, J.K. ; Oh, S.S. ; Ha, H.S. ; Kim, H.S. ; Ko, R.K. ; Yoo, S.I. ; Moon, S.H. ; Choi, K.D. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 52~56
According to the improvement of HTS conductor, HTS tapes which have the high current capacity have been recently researched in several nations. For large power application, AC loss is the most important issue in the development of AC superconducting power devices because it is closely related to the system operation efficiency. In 1st generation wire of HTS conductor, BSCCO, AC loss is too large to use for power application. Also, It is well known in recently years that YBCO CC, the 2nd generation wire, has also too much AC loss to apply to AC power devices. There are many trials to develop the new HTS wire having the low AC loss around the world. In this research, we present the measurment result of magnetization losses in SmBCO coated conductors. We measured the magnetization loss generated by perpendicularly exposed external magnetic field and compared with the analytic value of the strip model. Also, we presented the results compared with measured magnetization loss of an YBCO coated conductor.
Performance Tests of 1 MW Class HTS Synchronous Motor
Baik, S.K. ; Kwon, Y.K. ; Kim, H.M. ; Lee, E.Y. ; Lee, J.D. ; Kim, Y.C. ; Moon, T.S. ; Park, H.J. ; Kwon, W.S. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 57~61
A 1MW class HTS(High-Temperature Superconducting) synchronous motor has been developed. This motor was aimed to be utilized for industrial application such as large motors operating in large plants. The HTS field windings of the developed motor is cooled by way of Neon thermosiphon mechanism and the stator coil is cooled by water through hollow copper conductor. This paper describes performance test results of our motor, which was conducted at steady state in generator mode and motor mode.
Test of the Conduction Cooling System for HTS SMES
Yeom, Han-Kil ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 62~66
The characteristic of the superconducting magnetic energy storage(SMES) system is faster response, longer life time, more economical, and environment friendly than other uninterruptible power supply(UPS) using battery. So, the SMES system can be used to develop methods for improving power quality where a short interruption of power could lead to a long and costly shutdown. Recently, cryogen free SMES has developed using BSCCO(Bismuth Strontium Calcium Copper Oxide) wire. We fabricated and tested the conduction cooling system for the 600 kJ class HTS SMES. The experiment was accomplished for the simulation coils. The simulation coils were made of aluminium, it is equivalent to thermal mass of 600 kJ HTS SMES coil. The coil is cooled with two GM coolers through the copper conduction bar. In this paper, we report that the test results of cool-down and heat loads characteristics of the simulation coils. The developed conduction cooling system adapted to 600 kJ HTS SMES system and cope with the unexpected sudden heat impact, too.
A Study on the Principal Factors for the Stirling Refrigerator Performance
Kim, D.W. ; Park, S.J. ; Hong, Y.J. ; Kim, H.B. ; Ko, S.C. ;
Progress in Superconductivity and Cryogenics, volume 10, issue 1, 2008, Pages 67~70
Performance of integral type Stirling refrigerator used for cooling infrared detector is affected by principal factors such as design factors and operating factors. Operating factors include charging pressure and operating frequency. The purpose of this paper is to examine the basic design analysis on the integral type Stirling refrigerator and the changes in performance through experiments on operating factors.