A Wide-Range High-Voltage-Gain Bidirectional DC–DC Converter for V2G and G2V Hybrid EV Charger
Hamed Heydari‐doostabad, Terence O’Donnell
Abstract
This article proposes a new wide-range bidirectional dc–dc converter that has an improved voltage gain transfer ratio for use in electric vehicle (EV) applications. The converter preserves the common electrical ground between input and output terminals, and presents a low-voltage stress of switches, high utilization factor, and high efficiency. The proposed EV charger performance is evaluated for a bidirectional power flow in grid-connected vehicle-to-grid (V2G) and grid-to-vehicle (G2V) modes. The converter uses a dead-beat current controller in the dc–dc and dc–ac stages, which has a smooth, accurate, and fast response. Finally, experimental results for a 500 W, 40–200 V prototype are provided under a bidirectional power flow in a closed-loop system in the presence of the proposed dead-beat controllers. The obtained results substantiate the theoretical analysis and the applicability of this structure. The converter exhibits the capability for EV battery charging/discharging and demonstrates a peak efficiency of 97.2% and 96.8% in the step-down and step-up modes of operation, respectively.