Thank you all!
So here is the schematic, the general idea on the left, using a diode rectifier on the right. Maybe a step-down converter between the rectifier and the load.
My primary question however, is if there are other rectifier circuits that I might not know about and that are better than 4-diode rectifiers in this case. The source is an ultrasonic transducer.
Bridge rectifier is a way to go, the average drop will be 1.4-1.6 or so (due to high peak current, because of poor power factor).
That drop is what I don't like, because the source voltage can be
up to 20Vpp but also much smaller, in which case I'd lose a lot
I suggest get an oscilloscope, it will make things much easier.
It also would help if you share details about signal source and load you want to connect.
I have an oscilloscope and all lab bench equipment. The load, is a supercapacitor ESR 30
We'll need more details. What is the source of the AC signal and what happens to that signal when you load down the DC output? What DC voltage are you trying for? How are you loading and testing the DC output? If your source is not getting loaded down, you should be able to get power even just using plain 1N4148 diodes.
The source is an ultrasonic transducer.
DC voltage I need is no more than 6V DC. For DC output I tried connecting the supercapacitor or different resistors (100
to 100 k
) to see the efficiency for different loads.
Yes, if I don't load the source and connect it to only the rectifier, I can see high voltages (15-18V DC), but these are not very descriptive because when I connect a supercapacitor with 30
ESR the DC voltage drops.
In summary the DC voltage drop is fine, because I can typically reach the 6V DC, the problem is that the DC current is too low