Investigation on a Modified 11 Level Cascaded Inverter Fed by Photovoltaic Array for Standalone Applications

Abstract

This paper suggests a modified 11level reduced switch inverter fed by photovoltaic (PV) array feeding standalone AC loads. Multilevel inverters (MLIs) have great influence in distributed power system due to their high power capability with reduced harmonic content. Among the various topologies of MLI, cascaded MLIs are widely adopted for PV applications since batteries charged by PV panels can serve as DC voltage sources for MLI. The PV system charges the batteries through a buck converter, controlled by a smart perturb and observe (P&O) maximum power point tracking (MPPT) technique. The perturb and observe MPPT described in this work is capable of not only extracting maximum power from the panel but also regulate the charging mechanism of the battery. This work also aims at enhancing the performance of existing reduced switch topology, which is having higher harmonic and switching complexity by adopting a structural change. This topology uses less number of controlled switches compared to the existing method which aids in reducing losses and switching complexity. In addition to that, with a reduced switch count, it can be configured and realized easily. The proposed work is successfully realized in Matlab/Simulink and hardware environment. The simulation and hardware results prove that proposed work is highly viable.