• 한국태양에너지학회 논문집
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• 제24권4호
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• pp.19-25
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• 2004

A numerical study is performed to investigate the effect of sun tracking on the thermal performance of the evacuated compound parabolic concentrator (CPC) collectors. The evacuated CPC collectors consist of a two-layered glass tube, a copper tube and a reflector. The collector has a copper tube as an absorber and a reflector inside a glass tube. The water is used as a working fluid. The length and the diameter of the glass tube are 1,700mm and 70mm, respectively. The length and the diameter of the copper tube are 1,700mm and 25.4mm, respectively. Ray tracing analysis is carried out in order to compare absorbed heat fluxes on the absorber surface of the stationary and tracking collectors. The collected energy is calculated and compared with that on a fixed surface tilted at $35^{\circ}$ on the ground and facing south. The results indicate that the collected solar energy of the sun tracking system is significantly larger than that of a stationary collector. The sun tracking evacuated CPC collectors show a better performance with an increase in the thermal efficiency of up to 14% compared with an identical stationary collector.

• 반도체디스플레이기술학회지
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• 제11권3호
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• pp.27-31
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• 2012

This paper presents a study on the design of photovoltaic system with reversal tracking reflector. The reversal tracking reflector is conceptually designed by using TRIZ. The 20 to 30% of incident rays cannot produce the current and reflected back to the glass surface because of high refractive index of solar cell which are produced from Si, GaAs. The solution of this problem has been derived using 6SC(6 steps creativity)TRIZ. The reflector which has the actuator can be trackback the sun. Reversal tracking reflector which mounted on the top of the system prevents the shadowing loss and improve the efficiency of track back function. The anti-glare reflector prevents the heat due to the concentrated reflected light rays.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.357-360
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• 2007

An asset tracking using wireless sensor network is concerned with geographical locations of sensor nodes. The limited size of sensor nodes makes them attractable for tracking service, at the same time their size causes power restrictions, limited computation power, and storage restrictions. Due to such constrained capabilities, the wireless sensor network basically assumes the failure of sensor nodes. This causes a set of concerns in designing asset tracking system on wireless sensor network and one of the most critical factors is location uncertainty of sensor nodes. In this paper, we classify the location uncertainty problem in asset tracking system into following cases. First, sensor node isn't read at all because of sensor node failure, leading to misunderstanding that asset is not present. Second, incorrect location is read due to interference of RSSI, providing unreliable location of asset. We implemented and installed our asset tracking system in a real environment and continuously monitored the status of asset and measured error rate of location of sensor nodes. We present experimental results that demonstrate the location uncertainty problem in asset tracking system using wireless sensor network.

• KIEAE Journal
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• 제12권1호
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• pp.113-118
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• 2012

The photovoltaic is one of the most important sustainable technologies appliable to architectures. The power performance mainly depends on the installation conditions of them. This study aims to evaluate the power performance of photovoltaic system by the installation conditions, the tracking methods and reflecting mirrors. For the study, the Solar Pro computer simulations have been conducted on installation angles, solar azimuth and solar altitude. Also, the field mock-up tests are performed to of its application to verify the simulation results. Both the results of the experiment and the simulation have proved that the efficiency of 90-degree fixed angle method was higher than that of 30-degree fixed angle, the efficiency of altitude tracking was better than that of azimuth tracking method, and changing both the altitude and the azimuth together is more efficient rather than the shortened tracing way. In addition, the light-concentrating method in which the incidence angle of the sun is controlled by an adhered reflector has been analyzed to have better efficiency than the general method of tracing according to the orbit of the sun. Therefore, this thesis is expected to offer the basic data to set a more effective tracing-type of photovoltaic power generation system in the future. For this, more researches are to be conducted hereafter on a high efficiency drive motor and the establishment of an economic system.

• 전력전자학회논문지
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• 제8권3호
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• pp.260-265
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• 2003

태양의 고도와 방위각에 따라 태양광 발전 시스템의 에너지량이 차이가 많이 난다. 본 연구는 소규모 독립형 시스템인 가로등에 맞는 경제적인 추적장치 개발에 관한 것이다. 위치추적시스템은 프로그램을 사용한 방식으로서 시스템을 기존 유사 시스템에 비해 저가화를 실현하였다. 개발된 태양 위치 추적 시스템을 가로등에 적용하여 고정식과 추적식의 에너지량을 일정 기간 동안 실측 비교한 결과 평균 86%의 효율개선 효과를 보았다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1544-1546
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• 2004

This paper describes the element of solar cell's characteristics, photovoltaic system and solar tracking through experiment. Furthermore, it proposes the experiment results of the PV system is contained solar modules, power conditioning system and the solar tracking system using air compress charging energy The experimental results show that the PV system is always operated at maximum power of solar cells and tracking the sun in order to generate efficiently power generation and propose a capability of its application.

• 한국군사과학기술학회지
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• 제11권1호
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• pp.85-92
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• 2008

An architecture for multiple radar tracking systems can be broadly categorized according to the methods in which the tracking functions are performed : central-level tracking and distributed tracking. In the central-level tracking, target tracking is performed using observations from all radar systems. This architecture provides optimal solution to target tracking. In distributed tracking, tracking is performed at each radar system and the composite track information is formed through track fusion integrating multiple radar-level tracks. Track-to-track fusion and track-to-track association are required to perform in this architecture. In this paper, issues and recent research on the two tracking architectures are surveyed.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.693-697
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• 2007

A control system for solar thermal power plant is the control system to coordinate the whole system's operation, including management of distributed control systems, process control for optimal operation of total system, monitoring system operating conditions and doing administrative functions. This work, as a progress report, presents the results obtained so far in building a control system for the 1MW solar thermal power plant. To make the control system, we first defined the control system's hierarchy and classified the role of each layer. Then, as the first stage of making control system, we designed and developed the sun tracking control system for heliostat.

• 전기전자학회논문지
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• 제22권3호
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• pp.664-671
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• 2018

일반적으로 감지식 태양광 추적 시스템은 태양의 위치를 추적하기 위해 광센서를 사용하여, 최대 전력을 생산한다. 광센서 채택은 시스템 제작 가격을 상승시키고, 오동작에 의한 성능 저하를 초래할 수 있다. 본 논문에서는 IoT플랫폼 기반의 원격무선 모니터링이 가능하고, 광센서가 없는 새로운 태양광 추적 시스템을 제안한다. 태양광 발전을 위해 사용되는 여러 개의 태양광 패널의 출력 전류량을 비교하여 태양 위치를 광센서 없이 추적한다. 추적 성능의 검증을 위해서 12[V] 20[W] 태양광 발전 시스템을 제작하여 실험을 수행하였다. 본 논문에서 제안한 시스템은 IoT 플랫폼을 사용하여 원격모니터링이 가능하기 때문에 기존 태양광 추적 시스템에 비해 설치, 유지 보수 및 기능 확장의 장점이 있다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.39-40
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• 2005

Photovoltaic Power Generation system occupies an important position as an alternative energy source, converting directly sunlight into electricity,using a photovoltaic cell. The Purpose of this research is to present and confirm the effectiveness of concentration and tracking of sun in photovoltaic power generation. Comparative experiments were carried outwith two rating 75 watt solar modules in $25^{\circ}$ under condition of various times concentration, tracking and plain normal measuring generated voltages, currents and temperatures of back sheet of modules by internet monitoring system to find out which is best in economic sense. The experiments show that output power of concentration and tracking photovoltaic power generation is over 180% more then that of plain normal system.