An Improved Single-Switch Bridgeless SEPIC PFC Converter for Battery Charging Applications

This paper presents a new structure of an AC–DC bridgeless single-switch SEPIC converter for battery charging applications. The converter exhibits the features of power factor correction (PFC) by reducing the total harmonic distortion (THD) of AC input current to a considerable extent using the modified structure of the converter. The sizes of inductors are also considerably reduced in the proposed converter. The proposed single-switch converter topology makes it suitable for implementing the complex control algorithms required for battery charging. The circulating current is eliminated by introducing the blocking diodes in the proposed converter. A 200W/56 V prototype converter is synthesised to realise the proposed concept. This paper also includes a comparative study with different similar converters to verify the performance of the proposed converter.