Thanks bro,
I have already gone through this files but it seems something difficult that both pwm and square waves are generated at the output of h bridge ,hence I couldn't understand the way they managed the procedure, also is that inverter can provide 500w output although it has only 4 MOSFET arrangement in h bridge configuration. (I am really confused about the difference between h bridge configuration or by switching two MOSFET alternatively, how h bridge is more effective in inverter). And they have stepup 24vdc into 340v dc this explanation is not directly given in this PDF that's why I am really confused.