Bidirectional Isolated DC-DC Converter with High Static Gain: Analysis and Experimentation

A bidirectional isolated DC-DC converter with high efficiency and static gain, formed by the combination of a FBZVS-PWM and a current fed push-pull converter is presented in this paper. These features are accomplished through a partial regeneration of the energy stored in the transformer’s leakage inductance with an active clamping voltage circuit performed by a buck converter. Normally, current-fed push-pull converters have an energy loss in passive snubber circuits. The converter description, operation principles, waveforms, modeling, design and the experimental results of a 2000 Watts prototype are presented. The proposed converter can be implemented in high power applications that require bidirectional power flow and galvanic isolation, such as DC microgrids and electric vehicle battery chargers.