• Proceedings of the KIEE Conference
• /
• 2002.11b
• /
• pp.277-279
• /
• 2002

Recently, power requirement has been increasing. But the large generation unit is hardly installed because of economic and environment problem. Therefore, the concern for DG(distributed generation) is growing. Present, allowable interconnection capacity of DG for composite distributed generation is studied. In this paper, it is studied that the new interconnection capacity of DG for composite distribution system interconnected DG. We study new allowable interconnection capacity by power factor and placement. We study SERV(sending end reference voltage) variation and allowable interconnection capacity interconnected new DG.

• Progress in Superconductivity and Cryogenics
• /
• v.1 no.1
• /
• pp.22-27
• /
• 1999

Recently, small-sized superconducting magnetic storage($\mu$SMES) coils become commercially as an energy storage device for a power conditioner. In design and fabrication of the $\mu$SMES coils, to determine optimum current capacity of the superconducting(SC) conductors is one of the important things. We thus investigated the effect of conductor's current capacity, current density, and stability on the coil's maximum stored energy density in consideration of AC losses and switching device's capacities in a power converter. The results show that the smaller current capacity of the SC conductors is preferred for the $\mu$SMES coils but can increase their induced voltage excessively.

• Proceedings of the KIEE Conference
• /
• 2001.07d
• /
• pp.2187-2189
• /
• 2001

The proposed algorithm has produced the rules of relationship between the load voltage, current, discharging electric power and ampere-hours, electric power capacity of battery on the basis of the data. Which were acquired through the battery discharging experiment that is defined by the battery's ambient temperature and various load conditions. Especially, by calculating the parameter of second order polynomial equation relation between the remaining capacity and the electric power, the algorithm is proposed adapting for the discharging pattern. And as the depth of discharging is increasing, the calculation-method of electric power is applied to decrease the accumulated error in the calculation method of capacity accumulation. Also, the proposed algorithm has compensated the temperature considering the capacity change of battery to the temperature.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.790-792
• /
• 2002

The resistive type superconducting fault current limiter(SFCL) is a current limiter using the Quench mechanism of superconductors. When Quench occurs in superconductors, the resistance of superconductors increases abruptly. In order to increase SFCL capacity, current limiting elements were connected in series. If the Quench current of each element was different, voltage distribution was imbalanced. This imbalance could be removed by arrangement including series and parallel connection of elements. Based on this result, an SFCL of 1.8kV/50A was designed and experimented, expecially, in terms of increasing the voltage rating.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.607-612
• /
• 2002

This paper presents the first domestic model product of hybrid Insulation low-loss type pole transformer, with increased overload ability, increased life, reduced loss, focusing improved short-circuit characteristics. The capacity of this transformer is 100 KVZ, rates first voltage 13200 V and secondary voltage 230/115 type. The volume of model transformer that was produced in high temperature using hybrid insulation can be reduced to 10-20% in comparison with that of present transformer with the same capacity. In this paper, we did short-circuit test and tested general characteristics of model transformer. In addition, we suggested design application new concept and methods thorough this experiment.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.1
• /
• pp.388-394
• /
• 2015

The inrush current of a large inductive load can be reduced with a soft starter; however, the large inrush current caused by simultaneous bulk starts (SBSs) cannot be effectively reduced. In order to reduce the high inrush current and voltage sag owing to the SBSs of large capacity inductive loads within a power network, a novel hybrid sequential start control system is proposed, implemented on embedded systems, and evaluated with a testbed in this study. From the experimental and simulation results of the proposed control system, the inrush current could be effectively restricted below the maximum current capacity of a power distributing board. Moreover, with the proposed system, power cost typically dictated by the peak power consumption can be fairly reduced, and the quality of the power system connected to the inductive loads can be efficiently increased.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2002.02a
• /
• pp.211-214
• /
• 2002

It becomes difficult and high in cost to construct new ducts and/or tunnels for power cable in Metropolitan area. This paper presents the possible application of a HTS superconducting power cable for transmitting electric power in metropolitan areas, reflecting its important distinction such as compactness for installation in underground ducts and considerably economical efficiency comparable to present underground cables. In this paper, review of transmission capacity and voltage class of compact HTS cable which should be applied to existing ducts was performed.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1199-1200
• /
• 2011

The low voltage DC-DC Converter(LDC) is used for various electronic devices of electric vehicle. Depending on the growth of the car, the capacity of power conversion circuits must be increased. They have to provide the high efficiency and the high load capacity. The phase shift controlled full-bridge converter can be designed for LDC. The operating characteristics are considered through by simulation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.7
• /
• pp.105-113
• /
• 2011

The study about three-phase synthetic making test using DC power has been performed in order to increase the making test capacity on Vacuum Circuit Breaker. And, it made possible to solve the limitations that short-circuit testing facilities can not fulfill the testing requirements of VCB exceeding three-phase 36[kV] 31.5[kA]. By using DC power and high speed spark-gap switch, this method made the equivalence with the pre-arc that occurred during the making process under the fault condition of power system. As results, KERI(Korea Electrotechnology Research Institute) could have capacity to carry out type test for VCB under three-phase 52[kV] 40[kV], which satisfies the IEC Standard.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.05a
• /
• pp.705-710
• /
• 2003

In this study, to confirm the diffusion coefficient of chloride ion is affected by the concentration of NaCl solution, capacity of voltage, time of an electric current, the diffusion coefficient of chloride ion in concrete was investigated through an electrochemical accelerated test. and the results of these test were compared with the diffusion coefficient of chloride ion by test of sodium chloride solution digestion. As the results of this study, the diffusion coefficient of chloride ion wasn't affected by the concentration of NaCl solution, capacity of voltage, time of an electric current within the range of this study and was similar to the diffusion coefficient of chloride ion by test of sodium chloride solution digestion.