Control Strategy for Efficient Utilisation of Regenerative Power through Optimal Load Distribution in Hybrid Energy Storage System

Abstract

With an increased focus on green transportation, hybrid energy storage systems (HESS) for Electric Vehicles (EV) are gaining importance in recent years. In this paper, we propose a control strategy for optimal distribution of power demand between battery and supercapacitor (SC) in a HESS, as well as efficient utilization of the regenerative braking power. A DC/DC boost converter based power splitting strategy has been proposed. Two control blocks are proposed for charging and discharging of energy storage, which reduces the rate of discharge current, thereby improving the health and life of the battery. Simulation results are presented for the proposed circuit and compared with the state-of-the-art topology. The results show that the proposed control strategy improves State-of-Charge (SOC) of the battery from 84% to 94.4% in comparison with only battery held systems. The depth of discharge (DOD) also improved by 10.4%, which helps to enhance the range of the HESS based EV from a single charge.