Multilevel inverter based single stage grid connected solar PV

This paper proposes a single-stage inverter topology for grid connected PV systems. Isolated voltage generated by the solar modules is effectively used in a neutral point clamped multilevel inverter to generate high quality AC voltage for feeding into the grid. The control scheme is implemented in synchronously rotating reference frame for independent control of active and reactive power. Loss calculation and THD analysis is done for 2 level, 3 level, 5 level and 7 level inverter and an optimal number of level in achieved for a given voltage and power rating.