• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.179-184
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• 2005

The daylight responsive dimming systems, which use daylight and automatically controls the brightness of electric lighting, according to the amount of daylight coming into the indoor, as well as always maintains target illuminance, is an energy saving type system. The control slope that decide the dimming percent for dimming ballast to run this system efficiently should be decided exactly. This research ran performance assessment applying daylight responsive dimming systems to actual space, and supplemented control slope in the sky condition for the elevation of system. Also we revaluated a system by modified control slope and compiled valid propriety and alternative for the elevation system.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.36-48
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• 2008

This study examines the influence of control algorithms on dimming performance to determine appropriate control setting when direct/indirect lighting is controlled by a daylight dimming system. Computer simulation were performed for a small office with double skin envelope under various daylight conditions. A retractable fabric shading and Venetian blind were applied for internal and external envelopes under three CIE standard sky conditions. Unshielded and partially-shielded photosensors were used, and three control algorithms were applied for the sensors. In general, dimming level was too excessive due to the direct impact of light from lighting fixture to the photosensor. Providing insufficient lighting output, the unshielded photosensor completely failed to secure required illuminance under any daylight condition. When a partially-shielded photosensor was applied under clear sky, three setting points functioned effectively. Less sensitivity for the partially-shielded photosensor was effective to control the dimming system optimally with reasonable energy saving. However, the daylight dimming control system for direct/indirect lighting does not appear to be energy effective when photosensors without enough shielded area is installed on ceiling where light from fixtures reaches directly.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.133-136
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• 2005

Recently, a drain of energy resources is issued seriously. The daylight responsive dimming systems can reduce electric energy uses. But, we cannot predict amounts of energy-saving and accuracy of system performance. Therefore, the purpose of this study is a development of software for the system performance of daylight responsive dimming systems. The principle of this software based on luminous flux transfer method and finite elements method. The control algorithm of this software and daylight responsive dimming systems use the same algorithm. In addition the advantages of this software are use to same algorithm of daylight responsive dimming systems, electric power-luminous flux data and rates of frequency of sky conditions. Therefore, this software can predict more correct calculation about illuminance and amounts of energy-saving of daylight responsive dimming systems.

• 설비공학논문집
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• 제22권11호
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• pp.788-797
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• 2010

This study examines the influence of fluctuating daylight illuminance on daylight dimming control systems. Field measurements were performed for a full-scale mocked-up model under various daylight conditions in winter. Fluctuating ranges for a partially-shielded photosensor were great when the variation of sky ratio was great. When solar altitude was lower the illuminance and fluctuating range of illuminance were great due to the influence of direct components of daylight and the interrefelction between surfaces in rear area of space. It implies that daylight dimming system would not function effectively, unless the desktop illuminance by daylight is enough. Fluctuation ranges of photosensor illuminance were lower than 50 lx under clear sky conditions, but they were greater than 100 lx under partly-cloudy sky conditions. It means that the fluctuation range of electric light output of lighting fixture would greater under the partly-cloudy conditions and cause potential visual annoyance to occupants. Outdoor vertical illuminance reaching the windows would be an effective factor that can be used to predict the fluctuation of photosensor signals for effective controls of daylight dimming system.

• 설비공학논문집
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• 제22권8호
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• pp.553-561
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• 2010

This study examines the influence of light variation on visual responses in a small office space where a daylight dimming control system is applied. Field measurements and survey were performed in a full-scale mocked-up small office space under clear sky day conditions. Maximum fluctuation range for desktop was 133.5 lx and it just happened once for entire monitoring period. For the majority of time, the fluctuation range did not exceed 50 lx, which did not cause visual discomfort to subjects. The daylight dimming control system successfully kept required illuminance levels for an office environment when desktop illuminance by daylight ranged up to 300 lx. The most serious contributor to the sensation of glare was direct daylight through window. The dimming of electric light was not a significant contributor to visual discomfort for the subjects under clear sky day conditions. Visual comfort was significantly influenced by the sensation of glare, feeling for visual stimulation and distraction, and required illuminance level.

• 한국태양에너지학회 논문집
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• 제26권3호
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• pp.33-43
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• 2006

Daylight dimming control system was analyzed for an indirect lighting system in a small office space with a double skin envelope system. Computer simulations were performed for photosensors with three shielding conditions. The photosensors were placed on the center of ceiling, and backwall. Three sky conditions defined by CIE were considered. Overall, control performance was not very excellent for all conditions. Fully-shielded photosensor achieved good control performance for some cases, but partially-shielded and unshielded photosensors failed to achieve target illuminance. The variation in desktop illuminance due to daylight was examined for a variety of daylight conditions. Linear correlation between desktop illuminance and photosensor illuminance was analyzed using ANOVA.

• 조명전기설비학회논문지
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• 제27권12호
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• pp.44-53
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• 2013

This study has attempted to investigate how subjects perceive changes of brightness and their visual comfort according to daylight responsive LED(Light Emitting Diode) dimming systems in the office with venetian blind. Two studies was conducted. First study is that how subjects perceive changes of brightness and their visual comfort depending on angle control method of the venetian blind while the workplane illuminance level is being maintained through daylight responsive LED dimming system. Second study is that how subjects perceive changes of brightness and their visual comfort depending on the amount of daylight penetrated into the building while the illuminance level is being maintained through daylight responsive LED dimming system. The results of this study could be proposed as basic data in the control of the venetian blind and LED lighting in consideration of their perception on changes of brightness and visual comfort.

• 조명전기설비학회논문지
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• 제17권5호
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• pp.15-21
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• 2003

본 연구에서는 소규모 사무공간을 대상으로 주광과 인공조명의 성능 평가를 위한 디밍제어 시스템의 실험을 실시함으로써, 사무소 건물의 조명에너지 절약을 도모할 수 있는 성능 평가 자료를 제시하고자 한다. 본 연구에서는 성능 평가폭 위해 Mock-Up Room(3.6${\times}$7.2${\times}$2.6(m))을 사용하여 측정하였으며, 연구 결과는 다음과 같다; 1) 주광작업면조도와 센서조도간의 상관관계는 디밍 시스템의 성능에 영향을 미치는 중요한 요소이다. 2) 디밍 시스템을 적용한 본 실험에서는 주광과 인공조명을 포한함 총 작업면조도는 월평균 579[lux], 월간 에너지 절감율은 약 53[%]로 나타났다.

• 설비공학논문집
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• 제23권3호
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• pp.231-242
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• 2011

This study examines influences of a daylight dimming control system on the variation of indoor illuminance and lighting energy savings in a small office space. Field measurements and a series of computation were performed for typical types of sky conditions in summer. Results indicate that the daylight illuminance under clear and partly-cloudy sky were close to the target illuminance during a majority of time due to a higher ratio of window to wall. However, the target illuminance was not kept successfully due to the variation of photosensor signals which were strongly influenced by desktop illuminance. The system with partially-shielded conditions succeeded to keep target illuminance under clear sky conditions. The system failed under overcast sky conditions since the electric light output from fixtures caused excessive signals to photosensors due to insufficient daylight on a desktop. Unshielded and fully-shielded conditions were not recommended for effective controls of the systems. The influence of lighting fixtures on photosensors should be minimized to achieve successful lighting controls by daylight dimming systems.

• 조명전기설비학회논문지
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• 제22권12호
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• pp.20-28
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• 2008

에너지 자원의 고갈과 환경오염으로 인하여 건축조명 분야에서는 주광을 이용하여 에너지를 절약하는 연구가 활발히 진행되고 있다. 광센서 조장제어시스템은 실내로 입사되는 주광에 따라 인공조명을 자동으로 제어하는 에너지 절약형 시스템으로 쉐이딩 시스템에 의해 주광유입이 차단되어 그 적용성이 미비하다. 자동롤러쉐이딩 시스템은 태양의 변화에 따라 롤러쉐이드의 높이를 자동으로 제어하는 시스템으로 광센서 조광제어시스템과 통합되어 사용될 때, 불쾌한 직사일광은 차단하고 실내로 유용한 주광을 유입함으로써 에너지 절감과 쾌적한 시환경을 제공할 수 있다. 본 연구는 광센서 조광제어시스템과 자동롤러쉐이딩 시스템의 통합을 위하여, 각 시스템의 제어 소프트웨어를 개발하였고 이를 통합하였다.