Switched-Capacitor Integrated Single-Phase (2N+1)-Levels Boost Inverter for Grid-Tied Photovoltaic (PV) Applications

This paper presents a switched-capacitor integrated (2N+1)-level (N≥2) boost inverter for single-phase photovoltaic (PV) applications. It consists of N modular switching cells, where each cell consists of two switched capacitors and three active switching elements. A boost converter at the front side of the switching cells helps to maintain the capacitor voltage balance during different operation modes. With this arrangement, the inverter is capable to generate 2N+1 output voltage levels, and able to accommodate a wide range of input voltage. Detailed analysis followed by simulation and experimental results of a 5-level inverter as an example is presented to verify the proposed concept. Further, comparison with other multilevel inverter topologies is presented to show the merit of the proposed concept.