An Eight-Switch Nine-Level Common-Ground Inverter with Four-fold Voltage Gain

Transformerless inverters with common-ground concept have been gaining interest due to their advantages especially for grid-tied photovoltaic systems. The zero-commom mode voltage mitigates the leakage current enhancing the safety reducing the electromagnetic interference. This paper proposes a nine-level common-ground transformerless inverter with only eight switches, three diodes and four capacitors. In addition, the inverter presents an inherent quadruple gain dismissing additional conversion stages in a generation system. The paper outlines the various modes of operation, the design guidelines and a control strategy the closed-loop operation of the inverter. Finally, the performance of the proposed inverter is verified through simulation analysis.