• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.10
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• pp.534-539
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• 2006

An integrated inductor using the low-temperature co-fired ceramics(LTCC) technology for low-power electronics was fabricated. In the inductor NiZn ferrite sheet$({\mu}_r=230)$, was embedded to increase inductance. The inductor has Ag spiral coil with 14 turns$(7turns{\times}2layers)$, a dimension of 0.6mm in width, 10um in thickness, and 0.15mm pitch. To evaluate the inductance, including the parasitic resistance, the fabricated inductor was calculated and measured. It was confirmed that calculated values were very close to the measured values. Finally as an application of the LTCC integrated inductor to low power electronic circuits, a LTCC boost DC/DC converter with 1W output power and up to 0.5MHz switching frequency using the inductor fabricated was developed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.1
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• pp.10-15
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• 2020

Recently, with the increase in the use of urban solar power, solar modules are required to produce high power in limited areas. In this report, we proposed the fabrication of a high-power photovoltaic module using shingles technology, and developed accurate string characteristic simulations based on circuit modeling. By comparing the resistance components between the interconnected cells and the cell strips, the ECA resistance was determined to be 0.003 Ω. Based on the equivalent circuit of the modeled shingled string, string simulation was performed according to the type of cell strip. As a result, it was determined that the cell efficiency of the 4-cell strip was the highest at 19.66%, but the efficiency of the string simulated with the 6-cell strip was the highest at 20.48% in the string unit.

• Journal of the Korean Solar Energy Society
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• v.29 no.4
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• pp.28-33
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• 2009

In 2008, the global photovoltaic(PV) market reached 5.6GW and the cumulative PV power installed totalled almost 15GW compared to 9GW in 2007. Due to a favourable feed-in-tariff, Korea emerged in 2008 as the 4th largest PV market worldwide. PV power installation rose 495.5 percent to 268MW in 2008 compare to 45MW in 2007. Building integrated photovoltaic(BIPV) has the potential to become a major source of renewable energy in the urban environment. BIPV has significant influenced on the reflection by rear materials such as white back sheet and the heat transfer through the building envelope because of the change of the thermal resistance by adding or replacing the building elements. In this study, to use as suitable building materials into environmentally friendly house like green home, characteristic analysis of BIPV module according to rear materials achieved. Electrical output of PV module with white back sheet is high about 10% compared to other pv module because of 83% reflectivity of white back sheet compared to 8.4% reflectivity of other PV modules with different rear materials(black back sheet and glass). In the result of outdoor experiment during a year, electrical output of four different PV module is decreased about 3.72%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.1
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• pp.45-49
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• 2020

In this paper, we prepared miniature fuse fabricated with carbon nanotube (CNT) fiber for the use of low rated current under 1 A and high speed operation under 4ms. CNT fuses were fabricated in the form of universal modular fuse (UMF) with different diameter of CNT fibers defined by multiplying the CNT threads. Electrical properties of the CNT fuses were measured such as resistance, rated current, and operation time with current. Resistance of the CNT fuse decreased and rated current increased with the diameter of the CNT fuses, respectively. Consequently, the operation time with current increased with the diameter of the CNT fuses. The CNT fuses fabricated in this work had broad range of low rated current from 0.05 to 1.25 A by multiplying the CNT threads. Operation time was measured about 3.6ms which was applicable to the UMF.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2963-2967
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• 2010

In this paper, we have predicted and analyzed the MSX 60 photovoltaic module's output according to the temperature and solar radiation conditions by MATLAB program. 2 and 3-dimensional I-V curves of the PV module considered temperature, series resistance and solar radiation variation. are shown. Also, calculated PV's electrical parameters are Isc = 3.8 A, Voc = 21 V, Pmax = 60 W. Compared with the actual photovoltaic module's data, these simulated results agreed well with within the manufacturer's maximum error range 3%.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1600-1602
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• 2001

A pulsed power supply of 2.4MJ capacitor bank has been developed to make investigation into electric gun technology. It is made up of eight paralleled 300kJ modules, and can supply various shape of high current pulse by changing charging voltage, inductance, capacitance, and firing time of each module. The 300kJ module has been designed and fabricated for the maximum operating voltage of 22kV, peak current of 150kA, and pulse duration of 1msec. The experiments of the modules were done, and the equivalent circuit of the module was determined. The characteristics of the module were analyzed more deeply through the circuit simulation. The experiments of the paralleled modules with inductance of 20 $\mu$H and load resistance of 100 m$\Omega$ were performed, where the modules were discharged simultaneously and/or sequentially. The results of the experiments were analyzed. The 2.4MJ capacitor bank is currently used as the pulsed power supply for the ETCG (Electro Thermal Chemical Gun) research.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.12
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• pp.819-823
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• 2016

DSSC (dye-sensitized solar cell) is expected to be one of the next-generation photovoltaics because of its environment-friendly and low-cost properties. However, commercialization of DSSC is difficult because of the electrolyte leakage. We propose thermal curable base on silicon resin and apply a unit cell and large area ($200{\times}200mm$) dye-sensitized solar cell. The resin aimed at sealing of DSSC and gives a promising resolution for sealing of practical DSSC. In result, the photoelectric conversion efficiency of the unit cell and the module was 6.63% and 5.49%, respectively. In the durability test result, the photoelectric conversion efficiency of the module during 500, 1,000, 1,500 and 2,000 hours was 0.73%, 0.73%, 1.82% and 2.36% respectively. It was confirmed that the photoelectric conversion efficiency characteristics are constant. We have developed encapsulation material of thermal curing method excellent in chemical resistance. A sealing material was applied to the dye-sensitized solar cell and it solved the problem of durability the dye-sensitized solar cell. Sealing material may be applied to verify the possibility of practical application of the dye-sensitized solar cell.

• Progress in Superconductivity and Cryogenics
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• v.16 no.4
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• pp.66-70
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• 2014

The superconducting fault current limiter (SFCL) is an electrical power system device that detects the fault current automatically and limits the magnitude of the current below a certain safety level. The SFCL module does not have any electrical resistance below the critical temperature, which facilitates lossless power transmission in the electric power system. Once given the fault current, however, the superconducting conductor exhibits extremely high electrical resistance, and the magnitude of the current is accordingly limited to a low value. Therefore, SFCL should be maintained at a temperature below the critical temperature, which justifies the cryogenic cooling system as a mandatory component. This report is a study which reported on the cooling system for the 154 kV-class hybrid SFCL owned by Korea Electric Power Corporation (KEPCO). Using the cryocooler, the temperature of liquid nitrogen (LN2) was lowered to 71 K. The cryostat was pressurized to 5 bars to improve the dielectric strength of nitrogen and suppress nitrogen bubble foaming during operation of SFCL. The SFCL module was immersed in the liquid nitrogen of the cryostat to maintain the superconducting state. The performance test results of the key components such as cryocooler, LN2 circulation pump, cold box, and pressure builder are shown in this paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.327-328
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• 2007

• Design & Manufacturing
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• v.6 no.1
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• pp.95-100
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• 2012

In this study, a novel Cu composite sheet with embedded high electric conduction path was developed as another alternative for the interconnect materials possessing high electrical conductivity as well as high strength. The Cu composite sheet was fabricated by forming Ag conduction paths not within the interior but on the surface of a high strength Cu substrate by damascene electroplating process. As a result, the electrical conductivity increased by 40% thanks to mesh type Ag conduction paths, while the ultimate tensile strength decreased by 20%. The interfacial fracture resistance of Cu composite sheet prepared by damascene electroplating increased by above 50 times compared to Cu composite sheet by conventional electroplating. For feasibility test for practical application, a leadframe for LED module was manufactured by a progressive blanking and piercing processes, and the blanked surface profile was evaluated as a function of the volume fraction of Ag conduction paths. As Ag conduction path became finer, pressing formability improved.