This paper presents a control principle for utilizing PEM fuel cell as main power source and supercapacitors as auxiliary power source for electric vehicle applications. The strategy is based on dc link voltage regulation, and fuel cell is simply operating in almost steady state conditions in order to minimize the mechanical stresses of fuel cell and to ensure a good synchronization between fuel flow and fuel cell current. Supercapacitors are functioning during transient energy delivery or transient energy recovery. To authenticate control algorithms, the system structure is realized by analogical current loops and digital voltage loops (dSPACE). The experimental results with a 500 W PEM fuel cell point out the fuel cell starvation problem when operating with dynamic load, and also confirm that the supercapacitor can improve system performance for hybrid power sources. (c) 2005 Elsevier B.V. All rights reserved.