Discussion on types of UPS/Inverter working....

Hi,

I have been searching and working on inverter last few months. So, i have build inverter with push - pull with square wave using SG3524 it was working well with Mosfet.
but i found some problem like the output was square wave which is full of demerits. so, i want to work on modified sine wave or sine wave with less losses.

so, if any one here has over build or work on it please share it here and tell me about how to make good inverter as now working on H-bridges based inverter design....

thanks