High Reliability Multi-Input Converter With Low Input Current Ripple Based on SEPIC for Solar-Powered Unmanned Aerial Vehicle

This paper proposes a highly reliable multi-input DC/DC converter designed for long-endurance unmanned aerial vehicles (UAVs) in industrial and commercial applications. The proposed converter consists of a SEPIC converter andnexpandable units. Withn+1input ports, the proposed converter can efficiently interface with multiple photovoltaic (PV) arrays. Moreover, each input port of the converter features redundancy and can operate independently, thereby ensuring stable operational performance and high reliability. Furthermore, the proposed multi-input converter (MIC) can realize low input current ripple with the coupled inductor, which can both minimize the input filter capacitor of the converter and reduce the volume of the UAV power system, ultimately achieving a power density of 35.523 W/in3. Based on the theoretical analysis and simulation, a prototype with 1 kW output power is fabricated. Experimental results verify the effectiveness of the operational principles and the validity of its characteristics.