An Asymmetric Full-Bridge Bidirectional DC-AC Converter With Power Decoupling and Common-Mode Current Suppression for V2G Application

It is difficult to take into account the second-order current ripple, common-mode (CM) current, and efficiency of the converter in the application of vehicle-to-grid (V2G). To address this issue, an asymmetric full-bridge dc-ac converter is presented in this article, which can realize single-stage conversion by multiplexing switches and suppress CM current from the topology principle. A dual-target control strategy for this converter is proposed to implement bidirectional power transmission and power decoupling. Through power decoupling the dc port secondary ripple is transferred to the dc bus capacitor voltage. Besides, the circuit topology, control strategy, operation principle, high-frequency switching process, key circuit parameters design, and losses are analyzed theoretically. A 250 W prototype is built to verify the theoretical analysis. Based on the experimental results, the efficiency is 92.21% while the secondary ripple current of dc port is less than 3% and the common mode leakage current is almost zero at rated power. Finally, the proposed converter system is compared with other research solutions, and the experimental results indicate that the converter system has the optimal comprehensive performance.