A bridgeless SEPIC PFC rectifier with reduced conduction losses

bridgeless single-ended primary inductor converter (SEPIC) power factor correction (PFC) rectifier is introduced in this paper. In order to maximize its efficiency more than a conventional bridgeless SEPIC PFC Rectifier, a new driving scheme is proposed. In the proposed converter, conduction losses are reduced by eliminating bridge diodes. In addition, the impedance of the return current paths is lowered and conduction losses are reduced by applying a gate-on signal which is maintained during half line cycle to inactive switches. Consequently, the conduction losses of the proposed converter are significantly reduced and high efficiency is achieved. Besides high efficiency, the proposed converter provides high power factor (PF) and a continuous input current. Input current ripple can be easily removed by a simple filter capacitor. The operational principles, steady-state analysis and design equations of the proposed converter are described in detail. Experimental results from a 130 W prototype at a constant switching frequency of 100 kHz are presented to verify the performance of the proposed converter.