10. A Bidirectional Three-Level DC–DC Converter with Reduced Circulating Loss and Fully ZVS Achievement for Battery Charging/Discharging

A high-frequency isolated bidirectional three-level DC–DC converter is proposed for battery charging/discharging applications. To reduce the circulating loss, a double PWM plus double phase shifted control employing voltage matching control is proposed. ZVS for all power switches can be obtained even at no-load condition by employing the magnetizing inductance. The mode analysis is given to illustrate its working principle. The system parameter design criterion is given in view of the efficiency improvement and ZVS achievement for all switches. A detailed comparison of RMS value and peak value of the leakage inductance current is made with the voltage matching control and mismatching control, respectively. The effectiveness of the proposed control for the DC–DC converter is verified by experimental results of a 1 kW three-level prototype.