A Secondary-Side Phase-Shifted Bidirectional Soft-Switching DC–DC Converter Employing Step Voltage Switching for Eliminating Device Voltage Overshoot

In this article, we present a modulation strategy for bidirectional power flow for the step voltage switched (SVS) secondary-side phase-shifted (SPS) dc–dc converter that eliminates the device voltage overshoot problem. The voltage overshoot problem arises due to the resonance between the transformer leakage inductance and the output capacitance of the current-fed side metal–oxide–semiconductor field-effect transistor of the converter. Many snubber/clamp circuits were discussed in the literature to suppress this voltage overshoot. However, the power loss in these clamp circuits will affect the converter's efficiency. The bidirectional SVS SPS dc–dc converter presented in this article eliminates the voltage overshoot problem instead of suppressing it and, therefore, nullifies the need for a voltage clamp circuit. And most of all switching devices undergo soft-switching (either zero voltage switching or zero current switching). These factors result in achieving a peak efficiency of 96%. The proposed topology is tested for 1.7 kW at 100 kHz switching frequency with voltage-fed side voltage being 72 V and current-fed side voltage of 400 V. The results obtained prove the feasibility of the proposed work.