An Investigation of Supercapacitor Energy Storage Systems for Electric Vehicle Regenerative Braking

Abstract:
This research investigates the topology of a Supercapacitor Energy Storage (SES) system, which is charged during regenerative braking in an Electric Vehicle (EV) and subsequently delivers the stored energy to the vehicle's low-voltage systems. The innovation lies in a flexible storage management approach that utilises separate capacitor strings for charging and group discharging through various converters, simultaneously enabling bi-directional power transfer across multiple channels. Two types of DC-DC converters are employed: the transformer-less synchronous Buck-Boost converter and the resonant LLC converter. The storage management strategy, the design of the converters tailored to the system's requirements, and the final experimental verification are discussed.