In this paper a new class of power converters, serial multicellular chopper, will be studied. After recalling the dynamical equations of the converter, its hybrid dynamical behavior and properties are highlighted. This hybrid system induces new and difficult control problems. Then, two control strategies are proposed. The first is a sliding mode control and the second is a Petri Nets control. Some simulations are carried out to prove the efficiency and the robustness of the two controls for the case of a two cells converter connected to a nonlinear load. The comparison between sliding mode control and Petri nets control is carried out. Simulation results are provided to verify the conclusions.