Integrated Isolated AC/DC Converter Using IOFL for LED Driver Applications

Abstract

Power factor correction, voltage and current ripple reduction and eradicating short-life electrolytic capacitors are challenging issues in state-of-the-art ac/dc Light-Emitting-Diode (LED) drivers. Conventional single-stage drivers need an electrolytic capacitor to ensure low output current flicker. However, electrolyte capacitors having a high failure rate, reduce the life-span of the LED driver. To cover these challenges, in this paper an integrated LED driver is proposed. The proposed driver, is combined of three dc/dc converters with only one active switch. It features high power factor, low current flicker, and due to using only one active switch its cost, volume, complexity and power loss is low. The driver is analyzed step by step to show the operation principles based on duty cycle variations. Dynamic analysis and control design of the proposed driver is presented based on nonlinear control by Input-Output Feedback Linearization (IOFL). The simulation and experimental results have been provided to verify the versatility of the proposed driver.