I want design variac electronic Please anyone help me some ideas

[jengsyber]

I need design variac electronic by specification

1. Input 220V AC
2. output can adjust voltage 0 - 220Vac, current maximum about 10 Amp
3. frequency output can adjust about 5 - 500Hz


from picture below can i design it? if can not do it, how the other idea for this?



and I use dspic controller code is sine wave table to pwm control H-bridge if i not use buck converter but i program level Voltage by software can i do it?

 

[chuckey]

You will be lucky to get a power transformer that operates from 5-500 HZ. You need some feedback from the output back to the PWM side to stabilize the amplitude. FYI rectified 220V AC gives 1.4 times as much DC ~ 330V, but that depends on your transformer ratio.
Frank