Comparison between frequency splitting approach and fuzzy logic control as an energy control strategy in hybrid vehicles

Because of superior performance and outstanding advantages, electric vehicles become a hot research around the world. In this paper, the technique features of fuel cell and ultra-capacitor are described, and two energy distribution strategies of the hybrid power system based on frequency splitting approach and fuzzy logic control are presented and compared. The paper contains specific information and simulation about the hybrid power system. The objective was achieved by managing electricity with a fuel cell and supporting the system with an ultra-capacitor. In addition, compared to the strategy frequency splitting approach, fuzzy logic control has much more advantages to some extend according to the simulation results. The power and current of fuel cell and ultra-capacitor under fuzzy logic control varied less about 34% than under frequency splitting approach, and the maximum deviation of DC bus voltage under fuzzy logic control was less 44% than under frequency splitting approach.