Low Input Current Ripple Converters for Fuel Cell Power Units

Proton exchange membrane fuel cell (PEMFC) generators are today considered as a viable solution to the development of auxiliary, or back up, power units for automotive, computer and telecommunications systems. Several of these applications require a power conditioner with high efficiency, high conversion ratio and very low input current ripple to interface the fuel cell generator to a high-voltage DC bus. In this paper, two step-up non insulated DC/DC converter topologies, suitable to equip low power fuel cell power units are developed and deeply examined. A key feature of the two proposed converters is that they are obtained by mixing some basic topologies, in order to optimize both duty cycle and the winding ratio. Moreover, multichannel interleaved power conversion structures are adopted in order to reduce the size of input and output filters. Finally, both the proposed topologies feature an input inductance, that plays a major role in lowering the fuel cell output current ripple, thus reducing fuel consumption. The two proposed converters are theoretically analyzed and experimentally tested