Interleaved zero-voltage-switching active-clamped current-fed full-bridge isolated dc/dc converter for fuel cell applications: A case study analysis

An interleaved soft-switching active-clamped current-fed full-bridge isolated dc/dc converter has been studied. Its steady-state operation and analysis for wide input voltage and varying power transfer capacity are discussed. Interleaving two full-bridge current-fed converters reduces the input current ripple. Phase-shift modulation with parallel input series output interleaving is adopted. The power density of the converter increases with small devices´ ratings and less current/thermal stress on the semiconductor switches. The converter utilizes the energy stored in the transformer leakage and magnetizing inductance to maintain zero-voltage-switching over wide range of source voltage and load variation. It improves the converter efficiency and allows high switching frequency operation.