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AC generator to DC Super Capacitor

#1

Ok… I am trying out a fun little project. I have watched a few vids on how to make a simple AC generator (scores easier than a DC one) but I want to use it to load a charge to a super capacitor. This is a small device with ultimately a small DC load off the SC.
Do I just put the rectifier diode in line to the SC? Is it that simple?

#2

You should be careful not to exceed the maximum voltage rating of your super capacitor. They do not tolerate being charged beyond their voltage limit.

Another potential problem is that an uncharged capacitor looks like a short circuit, so a simple rectifier diode may need a current limiting resistor in series with it, to prevent the inrush current to the capacitor on startup from blowing out the diode.

Consider using a four diode full bridge rectifier for this. It could reduce your charging time considerably because it uses both polarities of your incoming AC.

If you -really- want to overengineer this, maybe you can use some sort of buck-boost regulator to protect the cap. See: Buck-Boost Regulators