Multiphase-converter topologies for high-performance applications have recently received an increasing interest. This paper proposes afterwards an analysis and a modeling of three-phase interleaved boost converter suitable for a fuel cell used in an electrical vehicle. The interleaved boost converter (IBC) is used in several applications which require increasing the output voltage such as fuel cells, photovoltaic cells and batteries. Thanks to the advantages related to the conventional boost converter, there are low input current ripples, a higher efficiency, a faster transient response, a reduced electromagnetic emission and an improved reliability. The multiphase boost topology includes a parallel combination of a number of boost converters with the same phase shift and the switching frequency. A circuit model of this converter which is equivalent to a small signal ac is elaborated to design and appropriate the controller in order to regulate the output voltage. The dc/dc converter topologies and their controllers are designed and investigated relying on MATLAB/Simulink.Finally, the proposed converter (IBC) is experimentally validated by obtained results from a prototype that has been built and tested in our laboratory based on DSP1104. The simulation and experimental results have shown that the proposed converter is more efficient than other dc/dc converter topologies to achieve higher performance and reliability of power dc/dc converters.