Soft-Switching Bidirectional DC-DC SEPICUsing a Lossless Active Snubber

A soft-switching bidirectional dc-dc converter using a lossless active snubber is proposed in this paper. In the proposed converter, zero-voltage-switching (ZVS) of main switches is achieved by utilizing an active snubber which consists of auxiliary switches, diodes, an inductor, and a capacitor. Although conduction losses associated with additional components increase, switching losses are significantly reduced due to the ZVS operation of main switches. Soft-switching technique makes it possible to have high efficiency by reducing switching losses and it is necessary for miniaturization and light weight. Therefore, total efficiency is improved. Moreover, there is no reverse-recovery problem of the intrinsic body diodes of the switches. Has non-inverted output. The advantage of the SEPIC over buck converter is that its output and input has the same voltage polarity, switching time is extremely fast , it do not generate voltage spikes and efficiency is approximately 93% also there is no heat loss.