• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.239-242
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• 2009

Power Control and Distribution Unit (PCDU) plays roles of power generation control for solar array panel, power storage control for battery system, power conversion for unregulated and regulated primary bus and power distribution to bus and payload system. The selection and design of the proper auxiliary power interface for PCDU depending on various mission is one of the most important step for electrical power subsystem design. In this paper, the general design approach of auxiliary power interface for PCDU which can be used for small-sized LEO satellites application is given. And, the auxiliary power design concept for always alived modules such as solar array regulator and house keeping module is also suggested.

• 설비공학논문집
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• 제23권6호
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• pp.392-399
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• 2011

Ground-coupled heat pump(GCHP) systems have been shown to be an environmentally-friendly, efficient alternative to traditional cooling and heating systems in both residential and commercial applications. Although some work related to performance evaluation of GCHP systems for commercial buildings has been done, relatively little has been reported on the residential applications. The aim of this study is to evaluate the cooling and heating performances of a vertical GCHP system applied to an artificial detached house($117\;m^2$) in Seoul. For this purpose, a typical design procedure was involved with a combination of design parameters such as building loads, heat pump capacity, borehole diameter, and ground thermal properties, etc. The cooling and heating performance simulation of the system was conducted with different prediction times of 8760 hours and 240 months. The performance characteristics including seasonal system COP, average annual power consumption, and temperature variations related to ground heat exchanger were calculated and compared.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.442-447
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• 2006

This paper investigates the shadow amount of edifice and according to time zone used by its Electric heating appliances, it is analyzed that Electric Heating Power Load affects Heal power load variation curve. Also, in case that the far infrared ray heating system, which are used as new electric heating system, occupies some of the existing Electric heating appliances, it is analyzed that the Electric heating power load affects the Peak load power in Korea.

• 한국태양에너지학회 논문집
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• 제38권4호
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• pp.55-66
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• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.572-578
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• 2003

본 발명은 비 접촉방식으로 데이터 정보를 인식하는 RFID(Radio Frequency Identification) 시스템과, 위성으로부터 정확한 시간과 거리를 측정하여 현 위치를 정확히 계산하는 GPS와, 이동통신 분야에서 많이 사용되고 있는 대역확산 기술인 CDMA를 이용하여 원자력발전소 임시저장소로부터 방사성폐기물 처분장까지의 전 과정을 방사성폐기물 개별 드럼 단위로 원격 감시할 수 있는 방사성폐기물 통합 관리 시스템이다.

• Journal of Advanced Marine Engineering and Technology
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• 제38권8호
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• pp.1000-1003
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• 2014

There are 70 vertical and 70 horizontal correctors for Pohang Light Source. Until mid of 2000, power supplies for these correctors were based on 1990's technology, so the global orbit feedback system was not possible with poor 12 bit resolution. A new task force team was assembled to develop new power supplies with BESSY type DAC cards. After the project, two vertical correctors in each lattice were connected with new power supplies, and the global orbit feedback was available within the accuracy of 5 microns. However, this replacement was not enough to satisfy the beam stability requirement of 2 microns for PLS. We have launched another power supply design based on all digital technology. This attempt was completed within a year, and 80 units were assembled in house. Currently, the global orbit feedback system is running successfully with new digital power supplies and the compensation of chamber motion due to the thermal load by using digital displacement transducers attached on each BPMs.

• 설비공학논문집
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• 제28권10호
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• pp.387-393
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• 2016

A ground source heat pump system maintains a constant efficiency due to its stable heat source and radiant heat temperature which provide a more effective thermal performance than that of the air source heat pump system. As an eco-friendly renewable energy source, it can reduce electric power and carbon dioxide. In this study, we analyzed one year of data from a web based remote monitoring system to estimate the thermal performance of GSHP with the capacity of 3RT, which is installed in a low energy house located in Daejeon, Korea. This GSHP system is a hybrid system connected to a solar hot water system. Cold and hot water stored in a buffer tank is supplied to six ceiling cassette type fan coil units and a floor panel heating system installed in each room. The results are as follows. First, the GSHP system was operated for ten minutes intermittently in summer in order to decrease the heat load caused by super-insulation. Second, the energy consumption in winter where the system was operated throughout the entire day was 7.5 times higher than that in summer. Moreover, the annual COP of the heating and cooling system was 4.1 in summer and 4.2 in winter, showing little difference. Third, the outlet temperature of the ground heat exchanger in winter decreased from $13^{\circ}C$ in November to $9^{\circ}C$ in February, while that in summer increased from $14^{\circ}C$ to $17^{\circ}C$ showing that the temperature change in winter is greater than that in summer.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2839-2844
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• 2008

A PEMFC(proton exchange membrane fuel cell) is a good candidate for residential power generation to be cope with the shortage of fossil fuel and green house gas emission. The attractive benefit of the PEMFC is to produce electric power as well as hot water for home usage. Typically, thermal management of vehicular PEMFC is to reject the heat from the PEMFC to the ambient air. Different from that, the thermal management of PEMFC for RPG is to utilize the heat of PEMFC so that the PEMFC can be operated at its optimal efficiency. In this study, dynamic thermal management system is modeled to understand the response of the thermal management system during dynamic operation. The thermal management system of PEMFC for RPGFC is composed of two cooling circuits, one for controling the fuel cell temperature and the other for heating up the water for home usage. Dynamic responses and operating strategies of the PEMFC system are investigated during load changes.

• 정보학연구
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• 제6권4호
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• pp.81-91
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• 2003

본 논문은 가정내 설치되어 있는 전력선을 이용한 스마트 홈 구축에 적합한 9.6Kbps 전력선 통신 시스템 구현에 관한 것이다. 제안한 전력선 통신 시스템은 가변 감쇄 특성과 가전기기에 의해 발생되는 각종 잡음들, 그리고 각종 가전기기 접속에 의한 임피던스 특성 변화등에 강한 신호 방식으로 100KHz~200KHz 대역 확산 주파수와 선형형태의 Chirp 신호를 사용하였다. 전력선통신 환경과 유사한 의사 부하 망을 제작하여 구현한 시스템에 대한 성능 실험을 하였다. 실험결과 의사 부하망 환경에서의 통신은 매우 만족하게 이루어졌으며, 구현된 Chirped-SS 방식의 9.6Kbps전력선 통신 시스템이 스마트 홈 구축에 있어서 상용화 할만한 성능을 가짐을 확인할 수 있었다.

• 농촌계획
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• 제14권2호
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• pp.25-32
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• 2008

Wind energy, which is one of renewable energy, would be useful resources that can be applied to making energy recycling villages without using fossil fuels. This study analyzed energy potential on wind power considering weather condition in three rural villages and compared with energy consumption surveyed. A wind turbine system in the 5kW class can generate 26.1%, 73.9% and 39.5% of the yearly mean consumption of electric power per house in Makhyun, Boojang and Soso respectively. A 750kW wind turbine system can generate 1.7%, 30.3% and 22.1% of the total amount of electric power consumption in three study villages respectively. Wind power energy density was too low in Makhyun and Soso, so it is determined that the application of wind turbine system is almost impossible. Wind energy potential was generally low in Boojang either, but it is evaluated that there is a little possibility of wind power generation relatively. For practical application of renewable energy to rural green-village planning, assessment of energy potential for the local area should be preceded.