This paper presents a fuel cell (FC)–supercapacitor traction drive and its power control. The proposed solution allows increasing efficiency and performances of an FC-based powertrain by means of a dual cascaded voltage source inverter and a supercapacitor bank. An optimal control algorithm allows avoiding the fast transition of the FC output power under whatever operating condition. It is based on five operation modes, which are selected as a function of the actual traction power request. This way, both power peaks and slopes are controlled during vehicle accelerations. A supercapacitor charge stabilization strategy, which uses the same cascaded converter power circuit, is also proposed. Experimental implementation has been performed for validation.