• Proceedings of the KIEE Conference
• /
• 1987.11a
• /
• pp.61-66
• /
• 1987

The metals has been used to the electric motor frame and brackets. The purpose of this project is to substitute engineering plastic doter frame for metal because of the demand for small size and environmental reliability. As a result of considering of mechanical strength, heat and injection characteristic of engineering plastics. PBT GF 30 has been selected as the material of electric motor frame including brackets. Design of the frame has been carried out on enough consideration of mechanical strength, heat-resisting and endurance. For the prevention of lower efficiency, the length of airgap between stator and rotor is reduced and for the reduction of vibration, slot combination is changed and the length of stator is increased.

• Proceedings of the KIEE Conference
• /
• 1998.07b
• /
• pp.825-827
• /
• 1998

Air pollution is one of the most important global issues of the environmental concerns. Some advanced foreign countries have developed the air pollution control technology. KEPCO has been researching on the air pollution control technology and developed the FGD(Flue Gas Desulfurization) system for 200MW thermal power plant. In this paper, we describe the major control loops implemented to the domestic FGD system. The major control loops are to be classified into booster fan control, absorber PH control and limestone density control. The control loops were applied to the actual desulfurization processes and proved to their performance.

• Journal of the Semiconductor & Display Technology
• /
• v.19 no.2
• /
• pp.110-114
• /
• 2020

In this paper, a heat pump using a Peltier device was developed for heat dissipation in a sealed electric box. The heat pump was designed with a cooling fin attached to both sides of the Peltier device, and a fan was mounted on the cooling fin on the hot side to increase the efficiency. The heat dissipation efficiency could be improved by directly connecting the electronic component having high heat to the cooling fin using a heat conducting wire. The fabricated heat pump was designed to operate only in the temperature range set by the temperature control system to improve the problem of high power consumption of the Peltier element.

• Proceedings of the KIPE Conference
• /
• 2007.07a
• /
• pp.259-261
• /
• 2007

논문은 동해화력발전처의 이차공기송풍기를 가변 회전수 제어하여 소내 소비 전력을 절감하고 전동기의 직입기동에 의한 스트레스를 줄이기 위하여 실증 적용된 동해화력발전처 이차 공기 송풍기 구동용 H-브릿지 멀티레벨 인버터에 관한 것이다. H-브릿지 멀티레벨 인버터는 독립적으로 절연된 직류 부를 갖는 저압의 단상 인버터(셀 인버터)를 다수 직렬 접속하여 고압 3상 전압을 출력하는 Cascaded H-브릿지 전압형 인버터이다. 본 논문에서는 동해화력발전처에 실증 적용된 6.6kV, 1MVA급 인버터의 계통 병입 후 부하 변동 시험을 통하여 신뢰성을 입증하였다.

• Proceedings of the KIPE Conference
• /
• 2007.07a
• /
• pp.262-264
• /
• 2007

최근 전압 및 주파수 가변을 이용하여 전동기의 속도를 제어하여 전동기 경부하시 베인에서 소모되는 에너지 절감효과를 얻을 수 있는 인버터 시스템이 널리 사용되고 있다. 이에 전력연구원은 6.6kV, 1MVA급 인버터 개발 및 동해화력 발전처에 설치, 보일러 점화 전/후 시험, 계통 병입 후 부하 시험 등을 국내 최초로 성공적으로 완료하여 현재 이차 공기 송풍기 구동용 인버터는 상업 운전 중이다. 본 논문에서는 기존 동해화력 발전 설비와 신규 인버터 시스템의 인터페이스 부분에 해당하는 보일러 DCS 로직과 계통 병입 후 시운전 결과에 대하여 상세히 기술하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.07b
• /
• pp.701-704
• /
• 2004

압전 외팔보의 구조가 갈수록 복잡해짐에 따라 더 정확하고 효과적인 압전체의 해석이 요구되어지고 있다. 본 논문에서는 3차원 직육면체요소를 이용한 유한요소법을 통해 압전 변환기를 해석하고, 이것을 실험적으로 검증함으로써, 3차원 유한요소법을 이용한 해석 프로그램의 타당성을 확인하였다. 또한 3차원 유한요소법을 이용해서 압전 외팔보를 해석하고, 이것을 실험 결과를 통해서 검증하였다. 그리고 압전 외팔보를 팬으로 적용하기 위해서 끝단에서의 최대 변위와 EMCF(Electo-Mechanical Coupling Factor)를 목적함수로 한 진화 전략 알고리즘을 적용하였다. 이를 통해서 팬용 압전 외팔보의 최적 설계를 수행하였다.

• Journal of the Korean Society of Safety
• /
• v.38 no.2
• /
• pp.15-22
• /
• 2023

In this study, the process and the environment of a melting furnace, located in Workplace A in Chungnam Province was inspected, and the insulation resistances of electrical circuits and motors were measured, and their changes over five years (2017-2021) were analyzed. It was found that the exhaust fan, oil pumps #A and #B, and heater were installed in 2010. Their insulation resistances decreased from 2017. Specifically, the insulation resistance of Oil Pump #A decreased from 100 (㏁) in 2018 to 20(㏁) in 2021, an 80% reduction. The fast decrease in insulation resistance was due to the high temperature of the melting furnace affecting surrounding the electrical facilities. A safety management scheme on the electrical facility of the melting furnace was proposed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.11a
• /
• pp.109-110
• /
• 2020

In This study, we tried to review an efficient curing method in consideration of safety and constructability among the problems of winter construction. In other words, as a result of the mock-up test, the measured value of carbon monoxide was 0 ppm in the case of an electric hot air fan. Since there is no carbon monoxide, problems such as suffocation are expected to be solved. In terms of temperature characteristics, electric hot air fans exhibited high thermal efficiency performance with a slight difference in upper/lower temperatures compared to the existing ones. In the future, we plan to conduct thermal efficiency evaluation through actual site performance verification. We will propose an efficient curing method through applicability evaluation.

• Analytical Science and Technology
• /
• v.13 no.4
• /
• pp.412-422
• /
• 2000

The polymeric FAB materials of air shower used in clean room of wafer industry have been outgassed with the dynamic headspace (ca.$100^{\circ}C$) for half an hour, and analyzed using GC-MS. The air in the clean room running air shower was sampled using sorbent tube method, and the organic compounds adsorbed in the sorbent tube were extracted using Soxhlet extraction method, and analyzed using GC-MS. The analytical results from FAB materials of air shower (electric over current relay, acryl plate. polycarbonate window, filter, fan housing, steel galvanized cold plate and canvas buffer) indicated that most of chemicals were originated from polymer fragments of FAB materials. Their analytical results have been compared with those from the air of clean room running air shower. These comparative results could lead to identify whether the sources of trace organic contaminants in clean room air are originated from the polymeric FAB material of air shower.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.36 no.12
• /
• pp.1185-1192
• /
• 2012

The typical operating temperature of an automotive fuel cell is lower than that of an internal combustion engine, which necessitates a refined strategy for thermal management. In particular, the performance of the cooling module has to be higher for a fuel cell system because the temperature difference between the fuel cell and the surrounding is lower than in the case of the internal combustion engine. Even though the cooling system of an automotive fuel cell determines the operating temperature and temperature distribution of the fuel cell, it has attracted little research attention. This study presents the mathematical model of a cooling system for an automotive fuel cell system using Matlab/$Simulink^{(R)}$. In particular, a radiator model is developed for design optimization from the development stage to the operating stage for an automotive fuel cell. The cooling system model comprises a fan, pump, and radiator. The pump and fan model have an empirical relation, and the dynamics of the pump and fan are only explained by motor dynamics. The basic design study was conducted, and the geometric setup of the radiator was investigated. When the control logic was applied, the pump senses the coolant inlet temperature and the fan senses the coolant out temperature. Additionally, the cooling module is integrated with the fuel cell system model so that the performance of the cooling module can be investigated under realistic operating conditions.