A power decoupling solution for improved single-phase Y-Source inverter

This paper proposes a power decoupling solution based on improved single-phase Y-source inverter with no additional power semiconductors. Single-phase inverter would cause voltage and current ripples on the dc link because of double-frequency power ripple. Commonly, large electrolytic capacitors are connected to dc link in H- bridge inverter to accomplish power decoupling. However, electrolytic capacitors would affect the reliability and lifetime of PV systems. As a result, the improved Y-source inverter is utilized for power decoupling instead, with only two capacitors added between the midpoint and each inverter arm. A corresponding control method is proposed to ensure the power ripple transferring towards the two decoupling capacitors without affecting the output voltage. Finally, a 200W laboratory prototype is built based on a TMS320F2812 digital signal processor to verify the performance of the proposed power decoupling solution.