Novel High-Voltage-Gain High-Frequency Nonisolated Three-port DC-DC Converter with Zero Input Current Ripple and Soft Switching Capability

In this paper, a novel structure of three-port with zero voltage switching (ZVS) dc-dc converter is proposed. Three-port dc-dc converters are widely applicable in hybrid energy generating systems to provide substantial power to sensitive loads. One of the ports of the proposed converter is interfaced with a storage such as a battery which makes the converter capable of supplying the load even if the main renewable energy supply of the proposed converter (e.g. photovoltaic cells) is not able to generate power. The proposed converter operates in two operations of charging the battery port and the mode when the battery discharges to the load. In addition, it has ZVS operation for all utilized switches and can eliminate the input current ripple. The ZVS of the switches is provided by the leakage inductances of the used coupled inductors. Also, the voltage control of each of the terminals is achieved by three active switches. In this paper, the proposed topology is analyzed theoretically for all operating modes, also, the voltage and current equations of all components are calculated. Furthermore, the required soft switching and zero input currents ripple conditions are analyzed. Finally, the accuracy performance of the proposed converter and the analytical results is verified by the PSCAD/EMTDC simulation and experimental results for 1MHz switching frequency operation. Applying high frequency and using GaN Fets leads to achieve a more compact prototype of the proposed topology.