A High-Efficiency Multi-Input DC-DC Converter with Optimized Output Filtering for DC-AC Inversion Applications

A multi-input DC-DC converter combined with a DC-AC inverter and filter system for grid-injected applications is proposed in this work. Robust DC bus voltage is provided by the proposed converter effectively combining multiple renewable sources of energy such as fuel cells, PV cells, and ultra-capacitors. Power flow management is enabled efficiently through the multi-input configuration of the DC-DC stage using optimal duty cycle control. Sophisticated filtering techniques employed in the subsequent DC-AC conversion process assist in reducing harmonic distortions, thereby increasing the quality of the AC output. The performance of the converter is assessed using a thorough mathematical model comprising voltage gain equations, inductor and capacitor design considerations, and power loss analysis. Under different load conditions, the efficiency of the system is investigated and shows great power conversion efficiency surpassing 92%. Moreover, simulated results confirm the theoretical model by showing better power factor and voltage ripple control. By including a sophisticated filtering mechanism inside the DCAC inverter, harmonic distortions are greatly reduced, so guaranteeing compliance with grid criteria. Providing consistent and stable power conversion for sustainable uses, the suggested system shows to be a feasible solution for integration of hybrid renewable energy sources. Future research aims to improve efficiency and compactness by means of advanced materials for passive filter components and hence optimize the control strategy.