OT: DC - AC "inversion" ?

[Hal]

I think I understand how AC becomes DC now, with a rectifier bridge.  That makes sence.  But how do you go the other way?  I guess some sort of timing circuit/sine wave generator could work, but i would think that would be very inefficent, especially at higher wattages.

[niftydog]

with a sophisticated arrangement of switching and filtering circuits known as an "invertor"

These are fundamental to the UPS principle.  (uninteruptable power supply)

There's bound to be plenty of ways to acheive this, and plenty of descriptions on the net.


The simplest form of invertor simply switches positive, zero, negative, zero, positive, zero.... etc.

To make it a little better, you might filter that switched DC so it resembles a sine wave (sort of).

More sophisticated invertors use all kinds of tricks like phase shifting as well as having multiple "switched" levels.

have a google around if you're keen!  You'll be surprised at the efficiencies of switch mode supplies!  Much better than the linear supply prefered by most of us!

PS; AC to DC requires not just a rectifier, but filtering as well!