Transformerless inverter

[Johansen]

Zlatko,
If you rectify and filter 230VAC then you will have 323VDC. Then if you use an H-bridge to make a PWM sine-wave with the 323VDC, the sine-wave will be only 114V RMS.

A 230VAC sine-wave is 650V peak-to-peak.

You are looking at it as if its a pwm'd half bridge.

think of it as a bridge rectifier working backwards you get the same voltage out as you put in.

however, there is one small issue, if you want to reproduce a good sin wave with no harmonics, then you can only modulate the PWM up to 80%.
for this reason three phase inverters using 6 switches use third harmonic injection. because the neutral is not used, the load don't see the third harmonic.

All this is spelled out quite clearly in The Power Electronics Handbook. by
M. H. RASHID

you can find it in a multitude of threads on this site.
here is one: