A Bidirectional DC-DC Convreter with Zero Voltage Switching Capability for Energy Storage Application

In this paper, a bidirectional DC-DC converter with high power density for energy storage application is proposed. The presented converter provides power transfer in both directions only with adjusting phase shift angle. Zero voltage switching (ZVS) in both turn on and turn off moments of all switches is the major capability of the converter that makes it suitable for high power applications. ZVS of the converter is provided without any auxiliary devices. High frequency transformers are employed in the converter construction to match the converter two sides voltage. Moreover, transformer leakage inductance along with external auxiliary inductance acts as energy storage in power transfer from one side of the converter to the other side. Operation principle of the converter in steady state is analyzed and then, its dynamic model is derived. ZVS criteria of the proposed converter are studied and finally, experimental measurement results of laboratory scale prototype are presented.