Universal bus digitally controlled front end damped PFC Cuk converter as LED drivers

In this paper; a single-stage three-loop power factor correction (PFC) technique is proposed for DC-DC converters used as driver for LED lights. The technique is demonstrated on a dc-dc Cuk converter which is used as driver for LED lamps wherein a two-zero; two pole digital compensator is used in the three-loop control structure for power factor correction. The converter is designed to operate in a wide range of load voltage variation (54–126 V) such that the current flowing through the LED can be controlled to control its brightness. The power factor control strategy presented in this paper employs three control loops for output voltage; input line current & to control the effect of change in ac line voltage. The simulation studies are carried out to establish the appropriate operation of the proposed PFC converter which complies with the IEC 61000-3-2 standard.