Implementation of MLI and THD analysis for grid connected PV system and simulation study of voltage stability with change in grid impedance

The recent development in the Photovoltaic system (PV) is because of the concern over the high demand in electricity and it directly produces electric power from the solar energy without any environmental hazards. The gird connected PV system will lose its stability when grid impedance is more. This paper compares the conventional grid connected single phase three level inverter topology with five level inverter grid connected system with PV array as the voltage source.

A new control scheme is used to generate the PWM pulses for the five level grid connected inverter to get much lesser Total Harmonic Distortion(THD). It also presents the Voltage stability with change in gridimpedance and without grid impedance.