Three-Port High Step-Up and High Step-Down DC-DC Converter with Zero Input Current Ripple

In this article, a nonisolated three-port dc-dc converter with high voltage conversion ratio is proposed. In the proposed converter, by changing the place of input voltage source between each of the three ports, three different single-input two-output operation modes are achieved. The input current ripple of the proposed converter is eliminated at the low voltage side for the whole range of duty cycles. The voltage conversion ratios of the proposed converter can be increased by increasing the turns ratio of second winding of coupled inductors. Moreover, the proposed converter has achieved proper output voltage regulations for all output ports, simultaneously. The proposed converter can be utilized in the renewable energy conversion systems such as in photovoltaic and fuel cells. In this article, the voltage conversion ratios of the output ports, the voltage stress on switches, the average currents of switches and inductors, and the required condition for cancelling input current ripple at low voltage side are calculated theoretically. The theoretical results are verified and experimental results for 24 V input voltage and 304 V, 240 V output voltages with 400 W power are extracted for two different operation modes.