Ultra-Fast DC Charger with Improved Power Quality and Optimal Algorithmic Approach to Enable V2G and G2V

Abstract

In existing electric vehicle (EV) charger topology, due to the presence of line frequency transformer and bidirectional DC-DC/AC converters, the circuit complexity in the structure gets increased in EV charger; thereby, it results bigger in size for high capacity. Moreover, due to rectification mode, it consumes the power with poor power quality. To overcome these drawbacks, this paper proposes a single input-dual port (SIDP) isolated bidirectional DC-DC converter (IBDC) to achieve ultra-fast EV charging of the battery. Also, to improve the power quality, a novel DC-link-fed PFC control strategy is proposed in this paper. Moreover, enabling grid to vehicle (G2V) and vehicle to grid (V2G) operation at bidirectional way depends on the situation such as state of charge (SOC) levels, off-peak and peak hours and user-defined data, which have been implemented using optimal algorithmic approach (OAA). The closed-loop control strategies are implemented to transfer the power at an accurate range using PWM plus phase-shifting approach. Moreover, it has the advantages of smaller in size due to the presence of medium frequency transformer and power quality gets improved without any additional converter stage. Finally, to validate the proposed operation, the results are observed under various case studies and conditional input from the customer and presented in this paper. Furthermore, the experimental results have been presented to validate the operation.