Design and New Control of DC/DC Converters to Share Energy Between Supercapacitors and Batteries in Hybrid Vehicles

In this paper, the authors propose the supercapacitor integration strategy in a hybrid series vehicle. The designed vehicle is an experimental test bench developed at the Laboratory of Electrical Engineering and Systems (L2ES) in collaboration with the Research in Electrical Engineering and Electronics Center of Belfort (CREEBEL). This test bench currently has two diesel motors (each connected to one alternator) and lead-acid batteries with a voltage rating of 540 V and a fluctuation margin between $+$12% and $-$20% of the rated voltage. The alternators are connected to the dc link by rectifiers. An original strategy of the supercapacitor integration in this vehicle with their control is presented to find a better compromise between the dimensions of the embarked devices, the share energy efficiency, the dynamics of the supply, and the electric power storage. The supercapacitor packs are made up of two modules of 108 cells each and present a maximum voltage of 270 V. The main objective is to provide a peak power of 216 kW over 20 s from supercapacitors to the dc link. Various topologies of dc/dc converters are presented with effective methodologies of electric power management in the hybrid vehicle.