• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.67-68
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• 2011

This paper analysed a protective equipment in power distribution system linked distribution power system when a superconducting fault current limiter(SFCL) is installed. This paper focused on a recloser, because the recloser is a general protective equipment. When power distribution system linked distribution power system, a fault current is increased by adding fault current of distribution power system. The increased fault current makes many problems. But SFCLs are limiting fault current and help the protective equipment to operate normal process. We analysed the operation of protective equipment in power distribution system linked distribution power system with SFCLs.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.31-32
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• 2006

Pohang accelerator Laboratory is from 1994 analyzed electric power amount used for about 10 years. It is one of equipment that consume electric power of greate electric power to single test equipment. Accelerator Laboratory institute investigates the consumption rate of energy that is spent to each building could divide by linear accelerator and save ring and analyzed about the equipment utilization rate and average electric power. Countermeasure that this treatise can forecast power loss of electric power by equipment through analysis of electric power amount used and heighten the utilization rate of equipment wishes to do comparative analysis.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1308-1316
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• 2017

The distributed maximum power point tracking (DMPPT) concept is widely adopted in photovoltaic systems to avoid mismatch loss. However, the high cost and complexity of DMPPT hinder its further promotion in practice. Based on the concept of DMPPT, this paper presents an integrated submodule level half-bridge stack structure along with an optimal current point tracking (OCPT) control algorithm. In this full power processing integrated solution, the number of power switches and passive components is greatly reduced. On the other hand, only one current sensor and its related AD unit are needed to perform the ideal maximum power generation for all of the PV submodules in any irradiance case. The proposal can totally eliminate different small-scaled mismatch effects in real-word condition and the true maximum power point of each PV submodule can be achieved. As a result, the ideal maximum power output of the whole PV system can be achieved. Compared with current solutions, the proposal further develops the integration level of submodule DMPPT solutions with a lower cost and a smaller size. Moreover, the individual MPPT tracking for all of the submodules are guaranteed.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.48-50
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• 2005

New environment change of electric power system focused in consumer's energy supply and demand. But electric power reliability preservation and reliability improvement countermeasure also need for long-term. It is need that change equipments that is composing electric power system in well-timed time and by maintaining, prevent breakdown beforehand and prevent consumer's power interruption by equipment fail. However, as only quantitative estimation is available by reliability estimation method that is presented in existing, it is no to use in dictionary fault prevention. Therefore, applied optimum reliability preservation through existent equipment fault data analysis of electric power system in equipment replace side, and this when maintain equipment replace of electric power system for reliability preservation using responsiveness analysis to base ordering evaluate. In existing about main equipment plain that this paper is power system the valued failure rate use this by score and precedence of electric power system equipment for replace of system considered expense.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.47-52
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• 2005

Recently, power conversion equipment increased rapidly makes a lot of harmonics. Thus, it is growing that wrong operation and break down of sensitive devices. There are two kinds of causes of harmonics. One of them is lots of power conversion equipment as modem controller, inverter, converter and SWS(Switching Mode Power Supply). Another is nonlinear operating machines as transformer and motor. The more nonlinear loads like them grow, the more serious problems as harmonic current to source and low power factor because of increasing reactive power grow. It is installed for reactor and L-C Filter to decrease harmonic in general. This paper analysis and compares two of characteristics and harmonic from reactor and L-C Filter with operation of induction motor and power conversion equipment. In the result, L-C Filter more improves unbalance rate and THD than reactor.

• Journal of Power Electronics
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• v.9 no.4
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• pp.544-552
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• 2009

This paper presents a novel spring pressure contact interconnect technique for medium power integrated power electronics modules (IPEMs). The key technology of this interconnection is a spring which is made from Be-Cu alloy. By means of the string pressure contact, sufficient press-contact force and good electrical interconnection can be achieved. Another important advantage is that the spring exhibits excellent performance in enduring thermo-mechanical stress. In terms of manufacture procedure, it is also comparatively simple. A 4 kW half-bridge power inverter module is fabricated to demonstrate the performance of the proposed pressure contact technique. Electrical, thermal and mechanical test results of the packaged device are reported. The results of both the simulation and experiment have proven that a good performance can be achieved by the proposed pressure contact technique for the medium power IPEMs.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1858-1868
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• 2021

Resisting an accidental impact of large commercial aircrafts is an important aspect of advanced nuclear power plant (NPP) design. Especially after the 9·11 event, some regulations were enacted, which required the design of NPPs should consider the accidental impact of large commercial aircrafts. Normal working of equipment is important for stopping reactor under an impact when an NPP is in operation. However, there is a lack of reliable analysis and research on the impact test of nuclear prototype equipment. Therefore, in order to study the response of the equipment under high acceleration impact, a centrifugal pump is selected as the research object to perform the impact test. A horizontal half-sinusoidal pulse wave was applied to the working pump. The test results show that the horizontal response of the motor and flange is greater compared to other parts, as well as the vertical response of the coupling. The stress response of the pump body support and motor support is high, hence these parts should be considered in the design of the pump. Finally, combined with the damage and stress evaluation results of the pump under different amplitudes, the ultimate impact acceleration that the pump can withstand is given.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.842-850
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• 2021

Real Time Simulation (RTS) has long been used in the nuclear power industry for operator training and engineering purposes. And, Online Simulation (OLS) is based on RTS and with connection to the plant information system to acquire the measurement data in real time for calibrating the simulation models and following plant operation, for the purposes of analyzing plant events and providing indicative signs of malfunctioning. An OLS system has been developed to support PWR operations for CPR1000 plants. The OLS system provides graphical user interface (GUI) for operators to monitor critical plant operations for preventing faulty operation or analyzing plant events. Functionalities of the OLS system are depicted through the maneuvering of the GUI for various OLS functional modules in the system.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2152-2153
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• 2011

According to a sharp increase in demand for electricity supply secure, and $CO_2$ regulation in accordance with global environmental problems and to solve problems, etc. These factor less pollution, higher energy conversion hyoyulin way that the new electrical equipment, nano-composites The rapid degeneration of the unit study utilizing the power that is required is Free. Accordingly, cables, transformers and switchgear (GIS)-capacity of power equipment, such as, high-voltage high-density along with the miniaturization of equipment have made angry the reliability of these devices is becoming a very important issue. Insulation materials used in electrical equipment for high voltage withstand, power equipment, power equipment due to aging and overloading caused by a weakening of the insulation failure and replacement in accordance with the age due to increased costs because of the reliability of electrical equipment should be secured should. Therefore, improved performance and longevity of insulation material is recognized as an important challenge. In this study, power isolation and degeneration of the unit for use in various parts of the molding epoxy resin to improve the insulation performance of the epoxy resin by varying the added amount of nano-SiO2 nanocomposites made epoxy/SiO2 analysis and breakdown properties of the experiment want to improve the electrical properties through the geometry.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4252-4265
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• 2023

In the case of nuclear power plants near end of their design life, a reassessment of the performance of safetyrelated equipment may be necessary to determine whether to shut down or extend the operation of the power plant. Therefore, it is necessary to evaluate the level of performance decline due to degradation. Electrical cabinets, including MCC and switchgear, are representative safety-related equipment. Several studies have assessed the degradation and seismic performance of nuclear power plant equipment. Most of those researches are limited to individual components due to the size of safety-related equipment and test equipment. However, only a few studies assessed the degradation performance of electrical cabinets. The equipment of various nuclear power plants is anchored to concrete foundations, and crack in concrete foundations is one of the most representative of degradation that could be visually confirmed. However, it is difficult to find a study for analysis through testing the effect of cracks in concrete foundations on the response of electrical cabinet internal equipment fixed by anchors. In this study, using a simple cabinet model considering cast-in-place anchor in uncracked and cracked concretes, a tri-axial shaking table tests were performed and the seismic behavior were observed.