He-Rie Park

Surface Discharge Characteristics for Epoxy Resin in Dry-Air with Variations of Electrode Features and Epoxy Resin Size

This paper shows a basic data of the surface discharge characteristics for epoxy resin in Dry-Air as being focused on environmentally friendly insulating Gas. Used electrodes are needle to plane, sphere to plane and KS M3015 electrodes. With the changing electrodes in same condition, we can obtain different creeping lengths, surface discharge voltages and surface dielectric strengths, respectively. Surface dielectric strengths of Needle to plane electrodes are more higher than the others. Moreover, it is considered that the surface discharge characteristics with variation of epoxy resin thickness and diameter. Surface discharge voltage increases as the thickness and the diameter of epoxy resin.

Surface Discharge Characteristics of Solid Dielectrics in N 2 /O 2 Mixture Gas for Eco-Friendly Insulation Design

In this paper, we deal with a surface discharge that caused an aggravation of the dielectric strength in the mixture gas, When composit dielectrics were formed from the use of a solid dielectric. It was found from this study that the surface discharge voltage was deeply involved in the mixture ratio of , the electrical property of the solid dielectric, kind of the solid dielectric, an electric field at the triple junction and a medium effect. These results expect basic data that will be used to transmission and distribution power system equipment using the mixture gas.

Thermal Modeling of Quasi-Adiabatic Room and Lighting Fixture for Estimation of Internal Heat Gain by Luminaires

In order to reduce energy consumption and greenhouse gas emission in building domain, thermal insulation of building is being enhanced. In a well insulated and tightened environment, internal heat gain caused by solar radiation, luminaires, electronic appliances and metabolism can be more important to thermal condition of building. This paper presents mathematical/physical models of quasi-adiabtic room and lighting fixtures using heat balance equation and thermal-electric analogy to quantify and modelize the heat gain due to luminaires. Experimental results are used to identify thermal parameters of theoretical models. And simulation results of models using Matlab/Simulink are conducted to verify the models and to investigate the thermal effect of lighting fixtures into quasi-adiabatic room.

Dynamic Thermal Model of a Lighting System and its Thermal Influence within a Low Energy Building

This paper focuses on the heat gain of a lighting system, one of the most-used appliances in buildings, and its thermal effect within a low energy building. In this study, a dynamic thermal model of a lighting system is first established based on the first principle of thermodynamics. Then, thermal parameters of this model are estimated by experiments and an optimization process. Afterward, the obtained model of the system is validated by comparing simulation results to experimental one. Finally it is integrated into a low energy building model in order to quantify its thermal influence within a low energy building. As a result, heat flux of the lighting system, indoor temperature and heating energy demands of the building are obtained and compared with the results obtained by the conventional model of a lighting system. This paper helps to understand thermal dynamics of a lighting system and to further apply lighting systems for energy management of low energy buildings.

A Study on the Surface Discharge Characteristics by Dielectric Constant and Diameter of Solid Dielectrics to Improve Surface Dielectric Strength in Eco-Friendly Insulation Gas

This paper studied surface discharge characteristics by a dielectric constant and diameter of solid dielectrics in mixture gas. Applied electric field strength at mixture gas was changed from the dielectric constant and diameter of the solid dielectrics, and insulation performance of the mixture gas determined surface discharge voltage. In each of the diameter at the solid dielectrics, the surface discharge voltage was increased by lengthening surface distance, whereas increasing rate of the surface discharge voltage was different from gas pressure. Thus, In this paper, main factors of surface discharge are as follows. 1) Insulation performance of mixture gas, 2) Dielectric constant of solid dielectrics, 3) Surface discharge path. It was clear that the surface discharge voltage depend on the main factors. These results will be applied to useful data for an eco-friendly composite insulation design.

Surface Discharge Characteristics of Teflon Resin in Environment-Friendly Insulation Gas

This paper reviews a basic data of the surface discharge characteristics for tefton resin in not only pure , (80[%]:20[%], I-Air) and (60[%]:40[%]) mixture gas as environment-friendly insulation Gas also . Used electrodes are Knife to Knife. With the changing distance of electrodes and pressure, we can find it, surface discharge voltages and surface dielectric strengths, respectively. Surface discharge Voltages of I-Air are more higher than the other mixture gases. Moreover, we can obtain that the surface dielectric strengths of are two times about I-Air, approximately.

The Study for Development of Landscape Lighting Lamp using LED for Underwater Dam

Recently, the demand of landscape lighting for underwater dam is rapidly increased by expansion of hydrophilic space. But it occurred the problems such as weakness of safety and display effect of underwater dam lighting lamp currently in use. Therefore, for solving these problems and improving underwater dam lighting lamp, this paper is focused on safety, energy saving, display flexibility of underwater dam lighting lamp and analyzed the related deriving problems by research on the actual condition. As a result, it presents a developed LED mold type underwater light instead of underwater dam lighting lamp. By the results of this research, it is considered that practical use of underwater dam lighting is very useful in waterside space for dams, water fountain, swimming pool, and etc. Moreover, it can be extended/applied in various ways.

The phase transition & breakdown characteristics of SF 6 in temperature decline

In this paper we use SF₆ gas(GSF₆) according to a surrounding temperature and are research to clarify the reason of GIS (Gas Insulated Switchgear) of the malfunction. The experiments of breakdown characteristics by temperature & pressure change of GSF₆, and SF₆ liquid (LSF₆) in model GIS are described. From the experimentpsilas results, the breakdown characteristics 3-Pattern are classified the vapor stage of SF₆ according to Paschenpsilas law, in which the gas & liquid coexisted stage of breakdown voltage (V_B) increases, resulting in much deviation and the V_B low stage as the interior of the chamber gets filled with a mixture of SF₆ that is not liquefacted and remaining air that can not be ventilated. The ability of LSF₆ insulation is higher than the high-pressurized SF₆ gas. Authors interpreted the 3-Patterns to the experimental and we clarify the reason of the GIS of the malfunction.