Design and Analysis of Efficient Battery Charging/ Discharging for V2G and G2V Application

Abstract

Batteries of Electric Vehicles (EV) and Plug-in Hybrid Electric Vehicles (PHEV) participate in the regulation of power flow in microgrid or smart grid through battery charger. A 4S-V, lkW isolated bidirectional battery charger is proposed in this paper. The proposed battery charger circuit worked in islanded mode, comprises of two-stage conversion i.e., AC-DC and DC-DC conversion. Neutral-point clamped converter is used for bidirectional AC-DC conversion while for DC-DC conversion High-frequency leg along with high- frequency Centered Tap Transformer followed by Half bridge is used. The proposed battery charger can convert three phase utility power to charge the vehicle batteries by providing 48V and 20.83A. Similarly, the same battery charger can discharge back the connected battery to load when there is power demand of load in islanded mode of microgrid.