A DC-side symmetrical class-DE ZVS rectifier as a power factor corrector for lighting applications

An analysis of a DC-side symmetrical zero-voltage-switching (ZVS) Class-DE current-source driven rectifier for a single-stage electronic ballast is presented, which is one of the symmetrical resonant rectifiers as a power-factor corrector (PFC) to improve a low power-factor and a high line current harmonic of a single-stage converter. Improvement of the power quality is achieved by utilization of the output characteristics of the DC-side Class-DE ZVS resonant rectifier, which is inserted between the front-end bridge-rectifier and the bulk-filter capacitor. By using this topology, the conduction angle of the bridge-rectifier diode current is increased and the low line harmonic distortion and the high power-factor were naturally achieved, the peak and ripple values of the line current are also reduced, allowing for a reduced filter inductor volume of an electromagnetic interference (EMI) filter. In additional, low-cost standard-recovery diode can be employed as bridge-rectifier. Experimental results are presented which verify the theoretical analysis.