Hi,
since Programmable AC Sources are rather expensive, I was wondering if an idea of using Inverter (which is rather cheap) and supplying it with 12/24V from DC bench power supply and controlling DC current make any sense?
Any bright idea, someone tried that?
Won't work.
It would be a little like putting a dimmer on the mains wire to your TV to control the brightness.
Hi Michal,
I don't think that setup would do what you're expecting. It's likely that reducing the current supply to the inverter will just cause it to stop working - but maybe if it was made cheaply enough, the output might scale with the input voltage (probably not).
The cheapest / easiest way to change AC voltage is to use a transformer, but that's a fixed solution.
You can use a VARIAC (basically a variable transformer) if you only want to vary the voltage and not the frequency.
It's possible to turn DC into AC, but it will require a significant amount of design + control & some pretty beefy power transistors / heat sinks (depending on the power you want to deliver). Basically you adjust the DC power to the level you want, then use an H bridge circuit to switch it on and off to your output. Just putting out a square wave will work ok in some applications, but you can improve that by adding dead time between the positive and negative states to make your signal look more sinusoidal.
I put together a quick simulation to show the basics, but you can probably find a ton of info online if you really want to go down the road of making your own AC supply.
Thanks guys, was just curies, but guess you are right.
That dimmer's been workin' for me bro.