Reduced harmonic multilevel inverter for single phase grid connected system

Now a day due to the requirement of renewable energy sources distributed generations (DG) are increasingly used. In such DG grid connection is required through DC-AC inverters. This paper presents a multilevel inverter for single phase grid connected system. Multilevel inverter performance is compared investigated to the conventional two level inverters due to their reduced harmonic distortion.

The switching of the inverter is based on the control algorithm so that the requirement of grid can be fulfilled. The main aim is to inject power in to the grid, to reduce the harmonics of grid current and to synchronise the grid frequency with inverter frequency. The PLL block is use for synchronisation such that the grid voltage and grid current with good power quality. Therefore the effective controller design for harmonic elimination is to be carried out using MATLAB software and simulation studies are presented.