A Comparison of Classical Two Phase (2L) and Transformer-Coupled (XL) Interleaved Boost Converters for Fuel Cell Applications

This paper investigates power interfaces for a PEM fuel cell. The main focus of the investigation is to analyze and test the effects of part-load operation on component selection and stresses with an emphasis on the magnetic components. The standard two-phase interleaved boost with a discrete inductor per phase is compared with the transformer-coupled two-phase interleaved boost, consisting of a single input inductor in series with a phase-coupling transformer. The converter characteristics are investigated for the experimental V-I inputs derived from the polarization curve of an industrial PEM fuel cell. Experimental validation is presented for a 3 kW design. Magnetic sizing of air-cooled components for power converters up to 45 kW are additionally investigated.