Power quality improvement using buck-boost converter for fluorescent lighting

This paper covers the design, analysis and simulation of power factor regulated and low crest factor based electronic ballast for a compact fluorescent lamp (CFL). The proposed electronic ballast is the combination of a buck-boost AC-DC converter as a power factor regulator (PFR) operating in the continuous conduction mode (CCM) and a half bridge series resonant inverter (HBSRI), which is used for converting a constant dc link voltage into high frequency AC voltage to drive the fluorescent lamp. The design, modeling and simulation of this topology are performed in MATLAB-Simulink for an 18W, 220V, 50Hz compact fluorescent lamp. With the utilization of proper commutation techniques like zero voltage switching (ZVS), the switching losses are reduced at high operating frequency of 60 kHz. The power quality indices such as displacement power factor (DPF), distortion factor (DF), total harmonic distortion of AC mains current (THD
i
), power factor (PF) and crest factor (CF) are evaluated for proposed electronic ballast, which is in the confirmation with IEC-61000-3-2 class C requirements.