색온도 및 조도 제어 알고리즘을 이용한 LED 조명

Abstract

This thesis presents an LED lighting system with an LED color control algorithm that can independently change its color temperature and illuminance.. To show the validity of the proposed algorithm, it is proven that its solution always exists. The proposed system consists of a power factor correction (PFC) circuit, LED driving circuits, and a digital controller. The proposed algorithm was applied to the control of an LED module that is composed of red, green, blue, and white (RGBW) LEDs. Its color temperature variation ranges from 3500?7500 ?K , and its illuminance ranges from 500?1500 lux. Within these ranges, the color temperature and illuminance deviations are as low as ?0.8% when the junction temperature of LEDs is maintained at 40 ?C. In the 30?70 ?C range, the measured illuminance and color temperature deviations are as low as 2.1% and 3.6%, and the compensated ones are as low as 1% and 0.49%, when the desired illuminance and color temperature are 1000 lux and 6500 ?K, respectively.