An Asymmetrical Reduced Switch Multilevel Inverter based Grid-connected PV system

A grid-connected photovoltaic (PV) system using a six-switch asymmetrical 9-level inverter is presented in this paper. One of the major advantages of the proposed grid-tied PV system using the six switches 9-level inverter over other existing topologies is that the number of conducting switches is only two for obtaining any voltage level. Thus the proposed grid-tied PV system is more efficient than the other PV system. Moreover, the proposed PV system can be extended to a high-power using cascading of several 9-level modules as well as to a three-phase structure very easily. A closed-loop current control technique is developed to balance the DC-link voltage in the ratio of 1:2. An experimental prototype of the proposed 9-level inverter-based PV system is developed in the laboratory demonstrate effectiveness of the control technique and to validate the simulation results.