High step-up interleaved converter with soft-switching using a single auxiliary switch for a fuel cell system

This study aims to develop a soft-switching interleaved converter with a high-voltage conversion ratio using a single auxiliary switch. As a step-up voltage converter, it performs zero voltage switching and zero current switching operations on main switches by means of the manipulation of the single auxiliary switch. In this manner, both the switching loss and switching stress of main switches can be reduced, giving rise to an improvement in the conversion efficiency. Placed in parallel with a converter available, merely a single resonant branch is employed in the proposed soft-switching mechanism, a simple and elegant way to reach the goal. This proposal is further applied to a fuel cell system as a high performance DC voltage booster so as to drive a high-voltage DC load. PSIM simulations are conducted and subsequent experimental validation is presented at the end of this work.