Hybridisation of battery, supercapacitor and hybrid capacitor for load applications with high crest factors: a case study of electric vehicles

Abstract

This paper proposes a novel topology of hybridizing battery, supercapacitor and hybrid capacitor for optimum utilization of energy in electric vehicles. Hybridization of energy storage has been the theme of much research in the field of power electronics as it is an effective economic solution towards improving the utilization of energy. Batteries have fallen short in comparison to both supercapacitors and hybrid capacitors because of their low power density and limited charge-discharge cycle. Most of the previous research in this field focuses on hybridizing either supercapacitor or hybrid capacitor with the battery but not both. This paper deals with the combination of both supercapacitor and hybrid capacitor with the battery thus addressing the problem of the lack of autonomy between two recharge points in supercapacitors, three hybridization techniques are considered and the balance point of the supercapacitor and hybrid capacitor banks is presented. The prospects of using a multiple-input DC-DC converter is also analyzed. An experimental electric vehicle profile was used to verify the proposed topology and the results are presented. The application of the novel hybridization of the three energy storage devices can be extended to other applications having a load profile with high crest factors.