Bidirectional EV Charging System with Parallel Battery Interfaces Control for Hybrid Grids.

Abstract

Amid rising fossil fuel costs and intensifying climate challenges, integrating electric vehicles (EVs) into hybrid smart grids offers a scalable pathway to improve energy efficiency and enhance grid reliability. This study proposes a novel bidirectional power interface that enables seamless vehicle-to-grid (V2G) and grid-to-vehicle (G2V) energy exchange. The proposed topology employs a single bidirectional converter and three parallel isolated DC-DC converters to support fast charging and ancillary grid services. Comparative analysis highlights its technical superiority by reducing voltage/current stress, minimizing device count, achieving compact implementation, and eliminating isolation requirements in the DC stage relative to conventional grid-tied units. Parallel battery operation provides independent control, mitigates charge imbalance, and ensures reliable full-load current delivery without overcharging or deep discharging individual cells. The system is validated through detailed MATLAB/Simulink simulations using a DQ-frame control strategy for accurate power regulation. Results confirm enhanced battery management, extended system lifespan, and reduced environmental impact, contributing to developing resilient and low-carbon hybrid energy systems.