This paper proposes the study of a dual power energy system carried out for an experimental test bench ECCE (Evaluation of the Components of an Electric Power train) that is a hybrid series vehicle. This work will focus on the study of the various components (batteries, thermal engine, alternator, control), in order to make evolve this platform by testing several operating modes and also to determine the performance and operation limits. This work has been also carried out in order to achieve a simulation tool which will represent the operation of the hybrid energy system and which can be used to study for example the decayed mode, the availability of the sources of energy and the functionalities of the various parts of a hybrid vehicle. Further works are planned to integrate ultracapacitors energy storage and also fuel cell energy generation.