A Flicker-free Power Leds Driver Based on the Non-isolated Sepic Rectifier Using a Regenarative Snubber

Abstract

This paper presents an AC electronic lighting system using a non-isolated SEPIC PFC rectifier to drive and control power LEDs currents. One energy regenerative snubber for reducing the converter switching losses and improve the system efficiency is proposed. To reduce ripple current in the LEDs array a linear current regulator is placed in the SEPIC’s output terminals. In order to reduce the efficiency impairment, the conditions for achieving minimum energy loss in the current regulator are also detailed. The operation stages as well as the theoretical waveforms and main equations at steady state of the proposed SEPIC rectifier using a regenerative snubber are detailed. To verify the theoretical analysis carried out, experimental results of a prototype operating in 127 and 220 V for 35 LEDs / 42 W are also presented. In this paper, the point of minimum energy loss in the linear regulator is adjusted in open loop to validate the converter operation.

Keywords

• Electronic Lighting System
• Energy Regenerative Snubber
• Linear Current Regulator
• Nonisolated SEPIC
• Power LEDs