• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2097-2099
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• 2005

Class-F and class-B insulating materials based on the resin rich type mica-epoxy composites for the stator windings in large turbine generators have been developed by DHIC. In recent, stator winding bars applied with prototype insulation tapes and commercially available resin rich groundwall tapes were produced through the same manufacturing processes as the real bars. Comparative tests to obtain the insulation properties of both bars were carried out such as IR/PI. dissipation factor and partial discharge at room temperature. In this paper, the manufacturing processes and the insulation properties of the bars which were not aged are presented.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1060-1062
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• 2003

In this study, an insulation design program which can calculate electric field of the GIS bus parts easily was developed. It also can evaluate the insulation safety depending on gas density. For bus parts of $1{\varphi}$ GIS, it was intended to provide a optimal diameter of a conductor and an enclosure automatically for the convenience of GIS insulation designer. This program was coded by Visual Basic and electric field was calculated by the Charge Simulation Method(CSM), which is one of the most accurate method for an electric field analysis.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.603-607
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• 2009

About a Structure is performance external insulation is fundamantal performance for enrgy-saving. these day, most of residential structures have constructed by internal insulation method structure. The method structure internal insulation have construction and economical efficiency, but on the other hand, be generated heat loss by heat bridge especially, be generated loss heat-energy logical consequence in structure ondol. The external insulation structure method has a mert able to minimum to loss heat about heat-bridge. But the external insulation technique is unsatisfactory statues within the know-how and method of construction and materials compared with developed countries. The recently, the requirement of market related to the external insulation technique is resulted by the energy efficiency system, but it can lead to the lack of alternative technique In study on the korea type passive house building design for insulation block method of wall system has to experimental characteristic heat-energy of practice building. In result field-experimental, the heat-bridge appeared to characteristic spent heat-energy of blow 2L class and have a suffience performance it.

• KIEAE Journal
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• v.11 no.6
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• pp.81-86
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• 2011

By strengthening the insulation performance of a building, a great deal of energy can be saved and a comfortable indoor environment can be offered to people. On the other hand, the climate, which has a great influence on the indoor environment, is changed by global warming. Therefore, in planning building envelope structure and design, climate change should be considered. In this paper, the optimal insulation thickness of exterior walls was calculated by an economic assessment method using heating degree-days. Additionally, how much influence climate change has on planning building insulation was investigated. The examination showed that heating degree-days have decreased by about 10% due to climate change in the past few decades. It was also shown that the optimal insulation thickness of exterior walls was thin, at about 6%, in three representative Korean cities (Seoul, Daejeon, Jeju).

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1617-1619
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• 1998

In the nation, 154kV XLPE cable with an insulation thickness of 23mm have been used for transmission lines. The thickness is designed by old parameters which were determined by Kreuger, Oudin et al. in 1960s. By the way, the manufacturing technology has been developed. Especially in extruding and curing process we are using a triple common extruding head and applying gas-curing process. It allows the quality of XLPE cable improved. The paper evaluates the AC minimum insulation breakdown strength of XLPE power cable using model table. We can verify the uplifted insulation quality. And we expects the cable insulation thickness to be reduced applying the new parameter to the cable insulation design.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.165-166
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• 2019

Curtain wall means a non-bearing wall that forms the outer walls of a building to divide the exterior and interior space. The increased use of curtain walls is diverse, including structural safety, watertightness, and wind pressure. As the government's energy conservation policy and the aim of zero-energy houses, the importance of heat reduction is also greatly increased. So, the study of monotony is constantly being conducted. Thus, in this study, insulation performance was analyzed through simulation according to the shape of curtain wall and the shape of insulation inside, and the purpose of this study was to provide basic data on the application of insulation criteria by energy saving design of buildings.

• Journal of Ocean Engineering and Technology
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• v.33 no.4
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• pp.340-349
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• 2019

In the case of a fire accident on a ship or an offshore plant, the design of the bulkhead penetration piece must be verified via a fire test procedure (FTP), as specified by the Maritime Safety Committee (MSC). The purpose of this study is to verify both the numerical analysis results and the design specifications for penetration pieces that could be applied to the A60 class bulkhead division. In this study, the FTP was carried out in accordance with the test procedure prescribed in the MSC regulation. In order to review the fire resistance performance according to the material type, bulkhead penetration pieces for the FTP were made from brass, carbon steel for machine structures (S45C), and austenite stainless steel (SUS316). In addition, spray-type insulation and mechanical fastener-type insulation were applied to investigate the fire resistance performance according to the type of insulation. To verify the heat transfer numerical analysis results for the A60 class bulkhead penetrating piece from this test study, the design specifications of the penetrating piece material and the insulation type applicable to a ship and an offshore plant were identified.

• Journal of Power Electronics
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• v.12 no.4
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• pp.654-663
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• 2012

In this paper, a digital control strategy based on equivalent fundamental and odd harmonic resonators is proposed for single-phase DVRs. By using a delay block, which can be equivalent to a bank of resonators, it rejects the fundamental and odd harmonic disturbances effectively. The structure of the single closed-loop control system consists of a delay block, a proportional gain and a set of zero phase notch filters. The principle of the controller design is discussed in detail to ensure the stability of the system. Both the supply voltage and the load current feedforwards are used to improve the response speed and the ability to eliminate disturbances. The proposed controller is simple in terms of its structure and implementation. It has good performances in harmonic compensation and dynamic response. Experimental results from a 2kW DVR prototype confirm the validity of the design procedure and the effectiveness of the control strategy.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.244-247
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• 2004

The electrical insulating design is important to realize a HTS power cable because the cable is operated under the high voltage environment. For the insulation design of a HTS power cable, it is necessary to investigate the AC, impulse breakdown and partial discharge(PD) inception stress of liquid nitrogen/LPP composite insulation system. Based on these results, the electrical insulation of a HTS power cable is designed and Mini-model cables are manufactured. The manufactured Mini-model cables are evaluated that AC, impulse withstand voltage, breakdown and partial discharge inception stress and analyzed characteristics insulation of HTS cable bending condition according to this paper. From these tests, the AC, impulse withstand voltage test and partial discharge inception stress is satisfied "standard technical specification of KEPCO" in Korea and the breakdown voltage was 120kV.

• Progress in Superconductivity and Cryogenics
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• v.9 no.3
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• pp.52-56
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• 2007

A high temperature superconducting (HTS) DC cable is ideal for transmitting large blocks of electrical power over a long distance. However, it must be designed to operate reliably within the constraints of the electrical systems. Therefore, a study of the electrical insulation is important to develop a HTS DC cable because it is operated in a cryogenic high voltage environment. This paper discusses the dielectric constructions of the cable and summarizes the experimental results on the DC and impulse dielectric characteristics of the insulation material. in sheet form and mini-model cable configuration. This shows how to design such insulation to be operated reliably. These studies are essential for the insulation design of a HTS DC cable operated in cryogenic environment.