• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.219-220
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• 2010

본 논문은 ZigBee 기반의 해상 유도등용 지능형 LED 조명 장치에 대한 개발과 원격에서 모니터링하고 관리할 수 있는 LED 조명 장치 관리 시스템을 설계하고, LED 조명에 대한 밝기 제어와 설치된 조명 기구의 주변 환경 데이터를 수집할 수 있는 지능화된 LED 조명 관리 시스템을 제시한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.475-476
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• 2009

Remote Control System based on Sproute Cultivator using LED characteristics was realized. It was carried out to investigate into the effect of LED Control with the physiological activity of sprouts. We have also composed a Combined Automatic Control System possible for the control of temperature and humidity at the same time. The applied LEDs for measurement are blue, green, red, white, yellow leds. And we producted the remote control OS using Linux and defined the characteristics of automatic control about sprouts.

• 전기학회논문지
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• 제65권1호
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• pp.158-164
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• 2016

That's the reason why LED lighting has to employ AC power inlet. However, LED is a kind of diode, semiconductor, it's driven by DC power. With whis reason all of LED lighting should have AC/DC converter in its systems. This converter causes energy loss, it's the target for lesson the energy loss. To reduce this energy loss, DC power distribution structure can be used. LED lighting system using LVDC is a kind of DC power distribution structure, but LVDC has severe voltage drop which makes non-uniform brightness in lighting system. In this paper, we suggest a novel structure for the uniform brightness in LVDC LED lighting system using IoT based network system. The constructed test-bed system of suggested structure shows this structure can con control the brightness with uniformity.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.846-847
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• 2016

LED 조명은 IT융합 시대로의 진화에 따라 단순조명에서 인간중심화/다기능화 시스템 조명으로 발전하였고 그로 인해 다양한 센서기능, 통신기능 등의 IT기술과 소프트웨어를 융합시켜 사용 환경변화에 따른 조명 제어로 에너지를 절감하고, 빛의 세기와 색조절로 사용자 중심의 맞춤형 조명이 요구 되고 있다. 이러한 지능화된 시스템 조명을 위해서는 사용자 중심의 센서 적용 및 제어가 가능해야하며 이를 위한 통신 모듈의 플랫폼화가 필요하다. 이에 본 논문에서는 LED 조명관제를 위해 블루투스 BLE를 활용한 통신모듈 플랫폼을 제안하였다.

• 조명전기설비학회논문지
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• 제29권3호
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• pp.30-38
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• 2015

As products using LEDs are developed actively, also there has been large request for LED products that can replace traditional lamps like fluorescent lamps and metal halide lamps. But so far there is no proper standard that manufacturer can use and test it. As a result manufacturer can't develop retrofit LED lamps and sell it even they have technology. In this study, by analyzing control gear for fluorescent lamp that is currently used in market which is magnetic or electronic ballast, I'd like to develop proper test method by investigating compatibility between all-type control gear and LED retrofit products.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 추계학술대회
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• pp.363-364
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• 2010

Most LED drivers uses current control method to adjust LED current. Using AC power grid such as off-line converter, Buck topology is popular because input voltage of LED driver is much higher than LED output voltage. Normally DCM current control is more popular than CCM current mode control in the range of below 50W, But DCM characteristics are dependent on the input voltage variation. This paper deals with what should be considered in DCM for LED driver with valley fill circuit.

• Design & Manufacturing
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• 제16권2호
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• pp.20-25
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• 2022

In line with the rapid economic growth of many countries, fossil fuel energy sources are also rapidly depleting. Therefore, the price is also rising rapidly, so it is necessary to develop new and renewable energy sources such as hydropower, geothermal power, nuclear power, wind power and solar energy to replace fossil fuel energy in the future. In this study, development of rotating concentrator module system, development of rotating module control control system, development of lamp and charge control controller, configuration and prototype production of rotating concentrating solar LED street light system, efficiency of rotating concentrating solar LED street light, and power production. The research was conducted in the order of evaluation of comprehensive performance tests such as consumption and consumption. As a result, the developed high-efficiency rotation-concentrating hybrid solar LED street light module system has a 50% higher light-gathering efficiency than existing products by tracing sunlight by self-developing a rotation-collecting module on existing solar LED street lamps according to the characteristics of Korea's topography. and the power generation was improved by more than 40%.

• 정보통신설비학회논문지
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• 제9권3호
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• pp.80-85
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• 2010

In this paper, we present an algorithm for efficient control of backlight LED in order to reduce the power consumption of LCD TV. In addition, a pragmatic implementation method is presented. In conventional local dimming control, backlight LEDs of LCD TV are divided into $M{\times}N$ blocks. And, the proper luminance for each block is computed according to input image and used for dimming control. But, LED light of each block is diffused and affects the neighboring blocks, so that luminance of each block becomes larger than that of intent. In the proposed algorithm, dimming control values are reduced by the amount of quantity affected by the neighboring blocks using light spread function, resulting in additional reduction of power consumption.

• Journal of Power Electronics
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• 제13권4호
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• pp.609-618
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• 2013

This paper proposes a primary side constant power control scheme for TRIAC dimmer compatible LED drivers. The LED driver is a Flyback converter operated in boundary conduction mode (BCM) to minimize the switching loss. With the proposed control scheme, the input power of the Flyback converter can be controlled by the TRIAC dimming angle, which is not affected by AC input voltage variations. Since the output voltage is almost constant for LED loads, the output current can be changed by controlling the input power with a given conversion efficiency. The isolated feedback circuit is eliminated with the proposed primary side control scheme, which dramatically simplifies the whole circuit. In addition, the input current automatically follows the input voltage due to the BCM operation, and the resistive input characteristic can be achieved which is attractive for TRIAC dimming applications. Experimental results from a 15W prototype verify the theoretical analysis.

• 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.