Power-Factor-Corrected and Fully Soft-Switched PWM Boost Converter

This paper presents a power-factor-corrected and fully soft switched (PFC-FSS) continuous conduction mode pulse-width modulated (PWM) boost converter. The converter has an active snubber cell, which guarantees the soft-switching operation of mosfets and diodes in the PFC-FSS converter. The snubber cell achieves the zero-voltage transition turn-on and zero-voltage switching (ZVS) turn-off for the boost mosfet . The snubber mosfet also turns on near zero current switching (ZCS) and turns off near ZVS. Besides, the boost diode turns off and turns on under ZCS and ZVS, respectively. During the turn-on transition of the boost mosfet, switching energies are transferred to the output and this results in significantly reduced current stress on the snubber mosfet. In the PFC-FSS PWM boost converter, boost mosfet and boost diode are not subjected to extra current and the voltage tension. All diodes of the snubber circuit work with soft switching. The presented converter also has power factor correction function and works with a high power factor. The detailed theoretical analysis of the proposed converter is presented, and the presented operation is verified with a prototype with 1 kW and 100 kHz.