Analysis and design of a novel single-phase full-bridge soft-switching rectifier

A novel single-phase full-bridge soft switching rectifier (FBSSR) using a new resonance unit is proposed in this paper. All main switches in the proposed soft switching rectifier operate at zero-voltage-switching (ZVS) turn-on and turn-off. Moreover, the auxiliary switches operate at zero-current-switching (ZCS) turn-on and turn-off. Major benefits of this novel rectifier are found in efficiency improvement, and reduced dv/dt. Besides, the proposed rectifier achieves a unity power factor, a sinusoidal input current and a bidirectional power flow capability. A small-signal model is derived and, in addition to the feedback control, an adaptive feed-forward controller is proposed to achieve almost zero output impedance and zero audio susceptibility. Finally, a prototype hardware circuit is constructed, and some experimental results are presented for demonstration.