A ZVT 48 V single-phase single-stage AC-to-DC converter

This work presents a pulse width modulated (PWM) high frequency (HF) transformer isolated, single-stage AC-to-DC converter with a new zero-voltage transition (ZVT) circuit. This converter integrates the front-end boost stage with the cascaded DC-to-DC bridge converter. The auxiliary circuit of this topology is placed out of the main power path and, therefore, has small power rating. Identification and analyses of all operating modes of this converter are presented. Based on these analyses design example of a 50 kHz, 48 V, 1 kW AC-to-DC converter is given. Results obtained from PSPICE simulation are presented to verify the performance of this converter.