Design, analysis, and implementation of a multiport DC-DC converter for renewable energy applications

This study studies a two-input boost DC/DC converter with high-output voltage gain. The presented converter has several advantages such as high step-up capability, continuous input current, bidirectional power flow from one of the ports, and its simple and low-cost structure. The presented converter can achieve a high-output voltage gain without using a coupled inductor or a transformer in its structure. Coupled inductors can cause voltage spikes on the main power switch, so active/passive clamp circuits are additionally required to eliminate the voltage spikes. The continuous input current of the presented converter makes it suitable for renewable energy sources such as photovoltaic panels and fuel cells.‏ An energy storage source such as a battery pack can be used in the presented converter. Charging and discharging of the energy storage source is possible using the presented converter. Pulsating charging current of the battery can improve the lifetime of the battery. In addition, discharging of the battery can be done without any constraints in the duty cycles. The thorough analysis and design of the proposed converter are discussed. A 300 W prototype of the presented converter is also used to verify the feasibility and proper operation of the converter.