• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 추계학술대회 논문집
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• pp.289-292
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• 2008

This paper represents the electric energy saving using light control system. Without Light Control System(LCS), it is very hard to classify the amount of electric energy saving for lighting, since it is determined by the end-user's preference in times. Typical LCS has an fixed algorithm to control each light's intensity by ON/Off Control, Step Control, or Dimming Control. We have studied the electric energy saving effect in a LCS equiped building with natural lighting. The electric power consumption at the peak power consumption time with LCS reduced up to 65% of the non-controled case.

• Journal of Power Electronics
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• 제15권2호
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• pp.555-566
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• 2015

A TRIAC dimming LED driver that can control the brightness of LED arrays for a wide range of source voltage variations is proposed in this paper. Unlike conventional PWM LED drivers, the proposed LED driver adopts a TRIAC switch, which inherently guarantees zero current switching and has been proven to be quite reliable over its long lifetime. Unlike previous TRIAC type LED drivers, the proposed LED driver is composed of an LC input filter and a variable switched capacitance, which is modulated by the TRIAC turn-on timing. Thus, the LED power regulation and dimming control, which are done by a volume resistor in the same way as the conventional TRIAC dimmers, can be simultaneously performed by the TRIAC control circuit. Because the proposed LED driver has high efficiency and a long lifetime with a high power factor (PF) and low total harmonic distortion (THD) characteristics, it is quite adequate for industrial lighting applications such as streets, factories, parking garages, and emergency stairs. A simple step-down capacitive power supply circuit composed of passive components only is also proposed, which is quite useful for providing DC power from an AC source without a bulky and heavy transformer. A prototype 60 W LED driver was implemented by the proposed design procedure and verified by simulation and experimental results, where the efficiency, PF, and THD are 92%, 0.94, and 6.3%, respectively. The LED power variation is well mitigated to below ${\pm}2%$ for 190 V < $V_s$ < 250 V by using the proposed simple control circuit.

• 태양에너지
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• 제18권4호
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• pp.67-75
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• 1998

Daylight illuminance are always changing. Nevertheless, when the energy savings due to daylight are calculated an accurate estimate of daylight availability is required. Where artificial lighting is photoelectrically controlled the relevant quantity is the cumulative distribution of daylight illuminance. This paper describes an experiment which measured daylight illuminance over one whole working year. Also using measured data on availability of daylight, equations are drived to predict the maximum possible savings from photoelectric controls for an interior lighting installation. The equations are applied to a space as a worked example and figures are given for the relative maximum savings in artificial lighting use of three control systems: on/off, dimming and mixed.

• 한국산학기술학회논문지
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• 제13권4호
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• pp.1797-1805
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• 2012

본 연구에서 LED는 에너지 소비가 큰 기존의 조명 시스템인 형광등과 백열등을 대체할 수 있는 새로운 조명 시스템으로 주목받고 있으며, 파워 LED 구동기인 DC-DC 컨버터에 관한 연구이다. 다양한 직류전원을 활용 할 수 있는 승압형 DC-DC 컨버터로 설계사양을 통한 인덕터 L과 커패시터 C의 값을 산출하여 PSPICE를 통한 최적의 값을 추정하였다. 컨버터의 스위칭 주파수는 50[kHz]로 최초 듀티비는 10[%]에서 출력전압의 검출 값에 따라 점차적으로 증가시키도록 하였다. 그 결과로 승압형 파워 LED 구동기를 시뮬레이션한 특성은 설계사양과 비교하여 5[%]이하의 오차로 근사적으로 나타났다. 또한, 입력전압 15[V]를 인가하여 안정된 24[V]의 안정된 출력전압을 얻었으며, 디밍제어를 통한 밝기 조절 및 소비전류의 조정이 가능한 결과를 얻을 수 있었다.

• Journal of Power Electronics
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• 제19권1호
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• pp.1-10
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• 2019

Current imbalance is the main factor affecting the lifespan of light-emitting diode (LED) lighting systems and is generally solved by active or passive approaches. Given many new lighting applications, independent control is particularly important in achieving different levels of luminance. Existing passive and active approaches have their own limitations in current sharing and independent control, which bring new challenges to the design of LED drivers. In this work, a multichannel resonant converter based on switched-capacitor control (SCC) is proposed for solving this challenge. In the resonant network of the upper and lower half-bridges, SCC is used instead of fixed capacitance. Then, the individual current of the LED array is obtained through regulation of the effective capacitance of the SCC under a fixed switching frequency. In this manner, the complexity of the control unit of the circuit and the precision of the multichannel outputs are further improved. Finally, the superior performance of the proposed LED driver is verified by simulations and a 4-channel experimental prototype with a rated output power of 20 W.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.166-168
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• 2007

A dimmable ballast system for the electrodeless fluorescent lamp is proposed. The proposed scheme is composed of the electronic ballast and the wireless communication part. They both are realized with one EPLD (Erasable Programmable Logic Device). The dimming levels of each lamps can be controlled by a management system through wireless communication technology. 10 ballasts are used for the group lighting system and the experiment results show the system works well.

• KIEAE Journal
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• 제12권6호
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• pp.107-112
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• 2012

The purpose of this study is to determine the optimum slat angle of the venetian blind which was applied at an outer skin of a curtain-wall system. The evaluation of the blind slat angle was performed in terms of the comfortable visual environment and decreased energy consumption. The office building prototype was considered for the analysis and simulation variables include application of blind, blind slat angle and dimming control of lighting. The annual energy consumption and incidence rate of discomfort glare were analyzed using EnergyPlus which is developed by the U. S. Department of Energy for the detailed building energy simulation. As a result, it turns out that when the blind (reflectance: 0.5) was installed, the annual energy consumption was greater than that of the base model. However, when the dimming control was applied, the maximum energy saving of 16.3% could be achieved at a slat angle of $0^{\circ}$. In addition, in case of the base model, the incidence rate of discomfort glare was 84%, while the case of the blind with the slat angle of $0^{\circ}$ showed that the incidence rate of discomfort glare was 42.4%. Consequently, the results showed that the slat angle of $55^{\circ}$ with dimming control was the optimum strategy for the comfortable visual environment and decreased energy consumption.

• 조명전기설비학회논문지
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• 제14권6호
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• pp.51-57
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• 2000

본 연구에서는 에쉬론사가 개발한 LonWorks 시스템을 이용하여 개방형 지능분산제어 네트워크을 구축 기술을 확립하고 이 시스템을 lP(정보네트워크)네트위크와 막힘없이(seamless) 통합할 수 있는 새로운 시스템을 제시하였다. 이를 증명하기 위하여 빌딩자동제어에서 중요한 제어.감시 대상인 원격검침(전력, 가스미터, 열량미터, 열량제, 온수미터), 조명설비의 조도제어(dimming control), 모터, 경보등 및 팬 등의 원격제어 실험시스템을 구축하고, 연구결과를 바탕으로 Web 네트워크에서 활용할 수 있는 원격검첨 및 조명제어 감시 기술을 개발하였다. 본 논운 결과논 LonWorks 네트워크로 제어되는 빌딩, 공장, 홈 등을 LAN이나 WAN을 개입시켜 필요한 제어대상을 원격 감시.제어시스템을 구축하는데 매우 유용한 기술올 제공 할 수 있다고 판단된다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 추계학술대회
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• pp.300-301
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• 2010

최근 반도체 산업의 비약적 발전으로 고출력 LED 광원 시스템 개발이 확대되고 있다. 그 중 무대조명 분야는 색 연출의 필요성으로 넓은 조도제어(Dimming) 범위가 필수적이다. 본 논문에서는 방송장비의 높은 센싱 속도로 인하여 화면에 생기는 빛의 떨림 현상 제거와 0~100%의 넓은 조도제어 범위를 구현하기 위해 Analog 조도제어와 PWM 조도제어를 결합한 조도제어 방법을 제안하였으며, 이를 위한 회로를 설계하고, 이를 실험적으로 검증하였다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.256-263
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• 2011

Recently, curtain wall structure is constructed according to increasing high rise building. Glass is usually used in opening of curtain wall structure and window area ratio is finally increased. Excessive Daylighting and solar radiation by large window area ratio cause discomfort glare and add to cooling load in the case of office that is heavy on lighting and cooling. Therefore, this study suggests to use low transmittance window for solve those problems. Indoor lighting environment and building energy performance were analyzed by increasing transmittance from 10% to 90% and comparing fixed venetian blind. Consequently, the range of transmittance that is possible to daylighting and prevent discomfort glare. Secondary energy consumption is efficient in the case that transmittance is the range of from 20% to 50%, primary energy consumption is nice on from 20% to 40%. If those result put together, the range of window transmittance from 30% to 50% is proper in the office in lighting environment and energy consumption aspects.