• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1651-1655
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• 2011

The reference impedances which is about 95% supply impedance value of residential consumers' supply impedances was published by IEC in 1980. The reference impedances are the standard values for use in determining the voltage disturbance characteristics of electrical equipment like the flicker. In IEC 60725, the reference impedances for premises having service current capacities less than 100A per phase and for service current capacities more than 100A per phase are recommended. And these reference impedances are targeted for the countries using 50Hz power frequency. Because of the frequency difference, the reactance values of the reference impedances will be increased in 60Hz power system like Korea, And also the reference impedances are different significantly each other according to declared voltage variation, power consumption and service wire length etc. Therefore It is needed to calculate the reference impedances suitable for domestic low-voltage power system. In this paper, the reference impedances for service current capacities less than 100A in 220/380V, 60Hz single-phase two wire and three-phase four wire low-voltage system are calculated, And the equations for service current capacities more than 100A to calculate the modulus value of maximum supply impedances are suggested base on IEC 60725 and the reference impedances for those are calculated on service current of 100A per phase.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.36-40
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• 2017

The launch operation for a space launch vehicle(SLV) is to be conducted by the systematic operation between SLV and the Technological Equipment(TE) such as the mechanical, fuel, and electrical ground support equipment at launch complex(LC). The basic source for the operation of the instruments in LC is the electrical power supply system, Technological Equipment Power Supply System(TEPSS), which is one of the Launch Control System. Thus TEPSS should supply the required electrical power to TE with reliability. In this paper, TEPSS which supplies operational electrical power to TE is introduced.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2647-2649
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• 1999

Electric power system is consisted of power supply and power enable circuit. Power supply provides operating voltage with internal chip. Depending on the operating voltage, power enable circuit provides operating signal, PWREN. Because energy is obtained from signal of external station, passive transponder must have the low power consumption. In this paper, the power supply module of the low power transponder is designed and analyzed.

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.1
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• pp.20-29
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• 2011

This paper proposes critical load following back-up system using MCFC stack. This system enables MCFC generation system to supply power to critical load without UPS and to generate rated power under grid fault state. This back-up system includes 'Load Leveler' that is connected with 3-phase inverter and is controlled by additional algorithm that includes critical load following. The proposed system and algorithm are verified by computer simulation based on 5kW system.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.228-230
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• 2001

This paper represents the application of the Static Var Compensator(SVC) on the electric railway power supply system. The purpose of the electric equipment can be summarized as to improve electrical power quality and to maintain the voltage. This paper shows that the SVC is necessary for voltage compensation in the railway power supply system and verify effectiveness of the SVC through the simulation. In this paper, the case studies were performed with the various line length and train position.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.5
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• pp.397-401
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• 2022

The construction of the ITER tokamak machine is ongoing at a 77% process rate to achieve the first plasma in 2025. The 18 sets of power supply systems comprising 400 MVA thyristor AC/DC converters for the superconducting magnets supplied by Korea (KO) are being installed with other systems, such as PF converters (China), DC busbars (Russia), and cooling water systems (India), in two buildings (Europe). The system interfaces have been defined during the design stage, and the systems have been manufactured. However, during the on-site installation work, several installation and integration issues emerged due to the manufacturing tolerance and design mistakes. To continue the installation and testing, the engineers of each system resolved the interface issues, planned the commissioning, and integrated the test plan. This paper describes the on-site installation status and issues and the commissioning plan of KO AC/DC converters.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.5
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• pp.31-40
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• 2008

Recently, Contactless Power Supply(CPS) system has been broadly studied as a power supply system for Flat Panel Display(FPD) material transfer equipments. In mass production line, CPS systems on material transfer equipment are applied only in the straight sections with single operating vehicle. The formal CPS system was not adequate for curved section nor multiple operating vehicles. Therefore, this paper presents CPS system that consists of straight and curved section with multiple operation vehicles. The circuit topology of CPS system consists of full bridge configured serial-parallel resonant DC/DC converter. The control method for CPS system consists of duty control method on the primary power supply system to maintain constant resonant current. And the secondary power supply systems of multiple vehicles are self controled to maintain constant output voltage. Practically, the test result of dual vehicles on straight and curved section of material transfer equipments were satisfactory, and proved it's applicability on commercial use.

• Journal of the Korean Solar Energy Society
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• v.38 no.1
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• pp.13-24
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• 2018

As part of the "Carbon free Island 2030" policy, the local government of Jeju Island is currently working to reduce carbon through renewable energy supply. However, renewable energy is difficult to predict due to intermittent characteristics. If the share of renewable energy increase, it is difficult to plan of supply of electricity to grid due to that characteristic of renewable. In this paper analyze the fluctuation rate and the capacity credit of wind power and PV to find out how much wind power and PV contribute to supply of electricity of power system in Jeju. As a result mean value of variation rate of wind power and PV is about 3%, 5% and capacity credit is about 10% and 2% respectively.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.415-418
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• 1999

It is expected that industrial accelerator having been distributed fast in domestic these days will be widely used for various fields. In this study we deal with the basic consideration for the drive characteristic of power supply system in the system of industrial accelerator installed at Dongshin University. Beam energy of this system is 34keV~40KeV, 100A. The modulator emits a 11KV-380A pulse of $4.5\mu\textrm{s}$ duration that is transformed to about 34KV-40KV pulse by a pulse transformer.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.3
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• pp.289-293
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• 2006

In this paper, we developed a ground power supply system for a mobile robot moving in the constrained region. By using an external scan circuit through the electrodes, it is also possible to detect the absolute position and heading angle of the robot without any additional position sensors. Since the heavy weighted-battery for electric power and the expensive absolute position sensors are not necessary to the robot by using for proposed system, the mobile robot system becomes cost-effective and dynamically fast.