Energy management strategy with optimized power interface for the battery supercapacitor hybrid system of Electric Vehicles

In the research field of Energy System for Electric Vehicles (EV), we focus on the application of Supercapacitor(SC), aslo called Ultracapacitor(UC), which is used as an energy storage device. SC has many advantages such as high power density, quick charging and extended lifetime. For higher performance of EV, SC and batteries are combined as Hybrid Energy Storage System (HESS), aiming to realize both high energy density and high power density. In this paper, a three-layer energy management strategy for HESS, with optimized interface for SC bank to DC power bus for EV platform, is proposed. The power sharing method based on converter control and variable frequency decoupling strategy is analyzed. Also the design of experiment platform is introduced. Experimental results validate that this control system is effective.