A Nine-Level Inverter for Single Phase PV Applications

Abstract

Multi Level Inverters (MLI) are commonly used in high voltage and high power applications due to their lower filtering requirements, smaller dv/dt transitions and better EMI/EMC performance. This paper presents a Single Phase Nine Level Inverter (SPNLI) using a coupled inductor. The proposed converter has low switch count, fewer capacitors and better reliability. Detailed operation of the proposed SPNLI and its control in standalone operation are discussed. An active energy buffer is also added to SPNLI to supply double line frequency component thereby reducing DC bus capacitance requirement. MAT-LAB SIMULINK based simulation results are presented to validate the proposed topology.