A PFC pre-regulator with 110 V/220 V input voltage and high frequency isolation for UPS applications

This work deals with the development of a PFC pre-regulator circuit with possibility of 110 V/220 V AC main input voltages, while maintaining the same efficiency for a wide load range. Other relevant features of this circuit topology are high frequency transformer isolation, soft commutation of the controlled switches, simple control strategy that can be implemented with well-known integrated circuits and the use of few batteries in series due to step-up stage. This circuit is recommended for on-line UPS applications and it is convenient for the development in rack-type structures due to small size and reduced weight. Qualitative analysis and experimental results obtained from 1.6 kW prototype are presented.