Probelm to understand how an inverter works and their mosfets

Regards,

First of all to say that I am new in the exciting world of electronics, so discululate ignorance.

After watching that there is another book on the subject of mosfet and power electronics, and achieve that another simulation of

diagrams downloaded online, I have seen that in the configuration to realize a single phase inverter for voltages of the 400V range

Low side voltage controller known, however, through the simulation, it was possible to observe how the voltage at the entrance doors of each mosfet was 400 V (Vge),

nevertheless after seeing the datashet of the mosfet puts that the maximum tension is of + -20V and of course I have remained a little impacted. One of the questions I have is how to get an investor

monofasic through the commutation of musts to high voltages, if the voltage of the doors is so low? anybody could facilitate a reference to understand how it's works?

A warm greeting and excuse the ignorance.