A Novel Single-Stage HPF Electronic Ballast With Coupled Inductors for Fluorescent Lamps

This paper proposes a novel single-stage electronic ballast with high power factor (HPF) for supplying fluorescent lamps. The presented electronic ballast integrates a dual boost converter with coupled inductors and a half-bridge series-resonant parallel-loaded inverter into a single-stage power conversion topology. The features of the ballast are cost-effectiveness, HPF (PF > 0.98), high circuit efficiency (>90%), low input current total harmonic distortion (THD <; 7%), low level of crest factor (CF <; 1.4), and zero-voltage switching obtained on both two power switches. Operational principles, design equations, and experimental results of one T5-type fluorescent lamp with a rated power of 21 W operating at 50 kHz switching frequency with 110 V-RMS line input voltage are presented. Satisfactory results demonstrate the feasibilities of the proposed ballast.