Comparative study between unipolar and bipolar switching scheme with LCL filter for single-phase grid connected inverter system

This paper presents the comparative study between unipolar and bipolar switching scheme for single-phase grid-connected inverter system with filter design on the grid side. For that, LCL filter is considered and its performance for current ripple reduction on grid-side is compared with normal L and LC filter. It is seen that the response for LCL filter show the best results with lower current ripple as compared to L and LC Filter. Further, the obtained results show that the obtained LCL-filter can provide sufficient attenuation of current harmonics and mean while injects a sinusoidal current into the grid for maintaining power quality standard. In addition to that, the method to design the inductor is also included in the paper. The studied system is modeled and simulated in MATLAB Computer simulation environment.