Dual Mode Seven-Level Transformerless Grid-tied Inverter with Common Ground Concept

This paper proposed a new transformerless seven-level common ground inverter topology with voltage buck and boost ability. The proposed inverter includes a dc voltage source, eleven semiconductor power switches, three electrolytic switched-capacitors, and an LC output filter. Being common-grounded, the ability to fully transmit reactive power, and the performance in a wide range of input voltage with the ability to generate seven-level voltage are among the salient features of our proposed inverter. The comparison of the proposed inverter with the recently presented topologies shows the superiority of our proposed inverter. Moreover, the basis of the proposed inverter’s performance is investigated in two modes and also more detailed analyzes will be presented in the final version. In addition, we performed a practical example with 450W using the level-shifted multicarrier PWM control method to validate the presented simulation results.