Power losses analysis and efficiency evaluation of high boost converters for PV and fuel cell applications

In renewable energy power conditioning system (PCS), like photovoltaic (PV) and fuel cell sources, the low input current ripple represents a very important issue to improve the source efficiency. This paper presents an analysis of the power losses and efficiency of two high boosting converters for PV and fuel cell applications, designed by the authors. The two converters are characterized by a single switching device and, the first topology, by a reduced input current ripple and, the second one, by a zero input ripple condition. In particular, the free ripple condition of the second topology is obtained by coupling the two inductors that are uncoupled in the first topology. A detailed mathematical analysis of the power losses and efficiency is presented together with an evaluation of the effects on the efficiency caused by coupling the inductors. The proposed concepts are demonstrated by simulation.