A modular multilevel power converter system for photovoltaic applications

In this paper a novel power conversion structure for grid-connected photovoltaic applications is presented. The proposed structure uses a four-wire voltage source inverter, two single-phase voltage source inverters and a scott transformer. PV modules arrangements can be divided in several groups. This power conversion structure is suitable for multi-string technology. The proposed structure allows multilevel output voltage. A sinusoidal pulse with modulator particularly adapted to this power converter structure is also proposed. Several simulation results are presented in order to verify the effectiveness of the proposed system.